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How the IBM PC Changed the World

CowboyNeal posted more than 7 years ago | from the 25th-anniversary-special dept.


Sabah Arif writes "On August 12, 1981, IBM released the IBM PC 5150. In less than two years, IBM had created a computer that would not only change IBM, but the entire world, mostly because it did not follow IBM tradition. It used an outside microprocessor (instead of the nascent IBM 801), operating system and software. Low End Mac recounts the birth of the IBM PC 5150."

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fp (-1, Offtopic)

Anonymous Coward | more than 7 years ago | (#15886969)


The Next Big Thing (5, Funny)

ian_mackereth (889101) | more than 7 years ago | (#15886973)

I reckon it was the Turbo button that was the best part of early PCs.

These days, no turbo button, so I'm stuck at a crawling 3GHz...

Re:The Next Big Thing (5, Informative)

Squarewav (241189) | more than 7 years ago | (#15887062)

I wish there was a modern version of the "Turbo" button

for thoes that don't know.. so many games and programs were made for the 8086/8088 that when they started upping the clockspeed many games ran too fast so they implimented the turbo button so that you could slow down the cpu to make old games and such useable

would be nice now to beable to push a button and have games from around 1995~ or so that I have lieing around playable again.. but alas that would be an interesting trick sence you'd have to impliment 3dfx voodoo 1, soundblaster and true dos in software/hardware

Re:The Next Big Thing (5, Informative)

Snover (469130) | more than 7 years ago | (#15887148)

And imagine that, they've done it [sf.net]. (Well, except for the Voodoo. But I bet that would happen eventually.)

Re:The Next Big Thing (1)

jonwil (467024) | more than 7 years ago | (#15887632)

Whilst its not DosBox, I wouldnt be surprised if the PC emulation in MESS couldnt use the voodoo chip emulation from MAME...

Re:The Next Big Thing (4, Interesting)

Valacosa (863657) | more than 7 years ago | (#15887272)

I wish there was a modern version of the "Turbo" button
So do I. I wonder how many FPS I'd get in Unreal Tournament 2K4 if I suddenly dropped my CPU* down to 8 MHz mid-game. My guess: 0.0037. Hey, we could start expressing Frames Per Second in scientific notation!

* Before some humourless nerd points this out, yes, I know a good chunk of the graphics in modern games is generated by a dedicated GPU. Lets pretend the turbo button affects the video card too, okay? It's a personal fantasy of mine.

Re:The Next Big Thing (1)

LiquidCoooled (634315) | more than 7 years ago | (#15887519)

Actually, its come full circle.
AMD's cool n quiet does the opposite and at least for original Unreal tournament it runs at the wrong speed (sometimes too slow, occasionally too quick).
My new amd 64 3400 runs UT worse than my older slower machine, I need an unturbo button which locks the processor speed for a while.
timings in the game are based upon a test loop at the start, the cpu speed changes under load so you get the wrong speed, I know theres a parameter to attempt to fix it, but its just annoying to have my latest computer running a 7 year old game like crap, I've become fragbait in the office.

Re:The Next Big Thing (1)

Yvanhoe (564877) | more than 7 years ago | (#15887647)

I'd rather have a potentiometer then. Sometimes I would need 8 MHz (for my 286 version of Alley Cats) , some other times 33Mhz, some others 166MHz ...
Ho, yeah, this should of course have a logarithmic scale, this goes without saying...

Re:The Next Big Thing (4, Funny)

pimpimpim (811140) | more than 7 years ago | (#15887294)

Hmmm, let me think, reintroducing something from the 80's as if it was your own innovation..... Maybe you should just wait for the next WWDC! Except that it won't be called 'turbo' anymore (that is really too 80's), but more something like "Engage". And it won't be an actual button, but more some sort of fancy transparent widget.

Anti-Turbo (1)

Kadin2048 (468275) | more than 7 years ago | (#15887467)

Actually, today it wouldn't be a bad idea to have a "Slow Down" button, to drop the clockspeed to a lower level. I guess this is effectively done in software anyway (how the chip turns parts of itself into low-power mode when it's not being fully used), but there are definitely times when I don't need my computer running at full speed. A simple switch that turned the clock down for a more power-friendly mode wouldn't be bad.

Or something that briefly over-clocked the processor, maybe running the fans at a speed that you wouldn't want to keep them at indefinitely, but would be safe occasionally ... that could come in handy as well. Lots of computers get used for games on occasion, but most of the time don't need the majority of their power.

Re:The Next Big Thing (1)

ricky-road-flats (770129) | more than 7 years ago | (#15887783)

The turbo button - happy memories!

My worst ever computing moment was in about 1989 when I got home from 2 weeks on holiday. My father was literally standing at the front door waiting for me, face like thunder. He looked ready to kill, and it quickly became apparent it was me he was ready to kill.

He was so angry it took him a few minutes to give me the gist of the problem - I had used his PC before going on holiday (BBS stuff), and he'd had to struggle for two whole weeks with an unusably slow PC - driving him insane. As I'd been the last to use it, it must be my fault.

I was in a real panic, I genuinely couldn't think what I might have done to cause it. I went to his study, and from across the room I saw what he problem was. I walked up to the PC, hit the turbo button and Lo! it was fine.

The turbo button actually had an LED which was lit when the PC was running at reduced speed.For two weeks he's been rebooting, uninstalling things, reinstalling things, and underneath his monitor next to the floppy drive he used frequently was a light telling him what the problem was!

I must have had a quick game of 'Level 42' which was unplayably fast on PCs faster than about 25 MHz...

That evening, I opened his PC and disconnected the turbo button from the motherboard, preventing any repeats.

CPM (5, Interesting)

Tablizer (95088) | more than 7 years ago | (#15886979)

I don't know why it is considered so great historically. CPM machines had spreadsheets and dBASE and word-processors and were doing quite well. The IBM PC stole that market and killed CPM because of the brand name. CPM would have been the base framework of the machines we use today had it not been for the IBM PC. In fact, the PC barrowed CPM-machine hardware in many cases.

Re:CPM (1)

jt2377 (933506) | more than 7 years ago | (#15887037)

i think MS-DOS killed CPM, Windows 3.1 kill Apple, Windows NT kill IBM's O/S 2 and now Windows XP/2003 is duking it out with Linux/Mac OSX. ahhhh...the never ending OS/PC war.

Re:CPM (4, Informative)

70Bang (805280) | more than 7 years ago | (#15887252)

Windows killed OS/2.[1]

Microsoft & IBM had a partnership underway. When it came to renewal & examination of what stood where, Microsoft gracefully bowed out. That left Windows and OS/2 on the market [as separate products]. I don't have dates for other releases, but I know Windows 3.1 was in the March<->May '92 timeframe and remember working on an OS/2 book (power users) in the late '92 or '93 timeframe. For some time, software packages which ran on one ran on the other. This was still a DOS environment as you couldn't boot Windows and there were several flavors of DOS.

Several Microsoft documents detailing meeting minutes indicated a discussion about making it such Windows wouldn't run upon anything but MS-DOS. The resolution was, "Only if it will absolutely, positively runs on MS-DOS [no matter what, no question whatsoever]; if it runs on something else, that's fine...it's better to err by running on too much than too little." The goal was to make it WOM[2]people would call and the response would be, "I'm sorry, Windows only runs on MS-DOS. I can put you in touch with the Sales[3] department so you can purchase a copy."

There are a few packages which are still OS/2-only, although they might be migrating if not having done so recently. The missus works at a large hospital and Pyxis (automated med dispenser, it tracks userid, password, station, date|time, medication, doseage, etc. Basically, it a data collection system where you enter the necessary info and a drawer with the meds opens up for you to remove the meds. If the hospital has moved from OS/2, it's been less than a year and was extremely painful. They've had plenty of problems anyway, so I don't remember which one of the agonizing pains brought home would have been the migration. (fortunately, they're better than SMS on the mainframe (from days of yore). I so hated trying to protect the machines the systems programmers|technical support were responsible for and SMS demanded God privileges in order to do their work, walking in like stormtroopers. That's when we found out they were all OJT.[4]

Someone mentioned CP/M and the turbo button. With the commercials today, one would expect an [Easy] button instead - slow things down & make them intolerably slow. I'm guessing any version of Windows would be like pushing the [Easy] button. Perhaps, push the [Easy] button and a list of Windows partitions (in order of slowness) would pop up and ask you which one you want to run. ;)
[1] The saying about OS/2 was DB/2, OS/2, PS/2: Half of a database running on half an operating system running on half of a PC.
[2] WOM = Write-Only Memory. Infinite storage capacity, but if you try to read...out comes the smoke and they call support. "Smoke came out of the cabinet? Are you certain? Did you try to read from it? Oh, I'm sorry. It's read-only. You can store as much as you want, but you cannot retrieve it. During a trip to an ACM conference in college '84, several of us who had a few too many glasses of gin (I hate vermouth) and bloody maries were working out the details to create a glossy brochure to send to the profs.
[3] Remember, Microsoft's strengths are Marketing, PR, and Sales; aka Huey, Dewey and Louie. I don't think people calling would understand if someone said, "I'll put you in touch with Donald Duck's nephew, Louie Duck." ;)
[4] On the Job Training. "We'll hire you dirt-cheap but won't send you to any classes. That costs money. The best thing to do is send you out into the mean, harsh world and you'll figure things out with time. Providing you don't booger up the clients' systems first. This isn't a case of being hired and learn things fast. This is being hired today and sent to a client site tomorrow without a parachute or docs.

Re:CPM (5, Informative)

Waffle Iron (339739) | more than 7 years ago | (#15887057)

CP/M was one of the OSes that IBM offered on the PC. So the PC itself didn't kill CP/M, rather it was probably Microsoft's much lower pricepoint for PC-DOS, along with all the customers who didn't feel that CP/M offered enough additional value to justify the extra cost.

Re:CPM (2, Informative)

mbstone (457308) | more than 7 years ago | (#15887142)

CP/M 86 was about the same price. But nobody wanted to type >pip >b:file=a:file (or whatever it was) instead of >copy a:file b: ?

Re:CPM (2, Informative)

Anonymous Coward | more than 7 years ago | (#15887548)

> CP/M 86 was about the same price

CP/M: $240

Identical, except for a leading digit.

Re:CPM (1)

Agripa (139780) | more than 7 years ago | (#15887578)

Sigh. I miss PIP. Of course, I miss FID also if only for sentimental reasons. I did not have access to hardware capable of running Unix for a long time or I am sure I would have made that transition earlier.

One of the first utilities I wrote for CP/M involved pacing the output to our printers because we had no flow control by keeping track of both carriage and roller movement. If I had had the source to PIP, I would have modified it instead of writing a separate program.

Thank Phoenix Technologies (4, Informative)

reporter (666905) | more than 7 years ago | (#15887215)

The IBM PC exerted a tremendous impact on the entire computer industry due to the confluence of 4 important factors.

1. The IBM PC was initially sold for about $1295. That was much cheaper than any other IBM computer. Apple and Commodore had cheaper computers, but small-business owners want the IBM name on their computers. Business people tended to view Apple computers and Commodore computers as toys.

2. The computer had the IBM label on it. These days, the IBM label does not carry the same cachet that the IBM name carried in the 1980s. At that time, IBM dominated the mindshare in the computer industry. People often said, "No one was ever fired for buying an IBM computer."

3. IBM encouraged other companies to build hardware and software for the IBM PC. It literally came with a full set of manuals documenting the entire BIOS and the internal wiring among the chips of the motherboard. Compare that open approach to, say, the typical Sony laptop. The plethora of software and hardware peripherals for the IBM PC enabled it to be adapted to a wide-range of useful applications: music synthesis, video games, desktop publishing, real-time intruder monitoring, etc.

4. Phoenix Technologies cloned the BIOS, enabling an army of companies to legally build functioning clones of the IBM PC. This army of cloners then spawned an entire universe of component suppliers. This intense competition among so many cloners and suppliers drastically lowered the price of the IBM PC and its clones. In turn, the lowered prices dramatically increased sales of the personal computers. Today, you can buy a Dell laptop for $500.

As prices dropped, more people bought computers; with more people owning computers, more companies building software and hardware for the computers appeared. Lather. Rinse. Repeat.

Among the four factors, item #4 is probably the most important factor in amplifying the impact of the IBM PC on the entire computer industry.

You can easily see the impact of #4 by comparing (1) the size of the ecosystem of companies building hardware and software for IBM PCs (now known as Lenovo PCs) and their clones and (2) the size of the ecosystem of companies building hardware and software for 68000 Macintoshes or PowerPC Macintoshes. Still more interesting, the enormous size and supercompetitive nature of the 1st ecosystem has swallowed even Apple: the new x86 Macintoshes are essentially (in a very general sense) an IBM clone. The x86 Macintoshes use the x86 (the central component of an IBM clone) and take advantage of the super-cheap VLSI chips from which IBM clones are built.

Re:Thank Phoenix Technologies (4, Interesting)

pimpimpim (811140) | more than 7 years ago | (#15887432)

It's easy to see that point (4), copying the idea and standards to other hardware companies, couldn't have happened if they didn't give away all the documentation as in point (3). And, point (4) not only increased the impact of IBM on the history of PCs, but it also decreased their market share as a PC supplier enormously.

What I find interesting to speculate on, is if they would've been bigger now if they had used some sort of "trusted hardware" contract, the same as which microsoft already tries to put through for some time now: forcing suppliers to develop hardware/software only under contract, and making sure that only hardware from those suppliers will actually function on their platform (not that the hardware capacity was there to check stuff like that at the time, I guess).

Or, would they have been marginalized by the more open competition if they would've chosen that path, and their current technique to support open standards, but deliver paid service and support for companies that need reliable software/hardware, is actually the best one?

Re:Thank Phoenix Technologies (1)

pe1chl (90186) | more than 7 years ago | (#15887771)

When the PC became such a success and IBM found itself more and more out of the loop, they tried that approach.
With the introduction of the PS/2, a new bus (MCA) was introduced and everything was more or less closed again.

It became a miserable failure, because the genie was already out of the bottle and the clone manufacturers could just ignore IBM and go on making their clones without having to incorporate more than the keyboard and mouse connector. The early issue of "is this clone really compatible with IBM" had turned around to "is IBM still compatible with the PC world", and after a while they turned back to making compatible systems.

Economically, open always wins (2, Interesting)

Colin Smith (2679) | more than 7 years ago | (#15887805)

Restrictions are designed to increase the profitability of the vendor and therefore always increase the costs to customers. Inevitably at some point a more open and lower cost alternative always appears. If IBM hadn't released the specs, something else would have appeared which we'd be using now. It's economically inevitable. This is actually why Linux will ultimately replace Windows and most other operating systems.


$1295 (4, Interesting)

Sithech (858269) | more than 7 years ago | (#15887455)

Yes, I remember going downtown in SF to see the PC. For $1295 you got a machine with 16 K of memory, no graphics adapter, no floppy drives. You could hook it to a cassette recorder. Pretty much a clone of the bottom-end configuration of the Apple II, at about the same cost (no, Apples weren't significantly cheaper). What it had going for it was a keyboard that included lower-case and function keys . And the graphics modes of the color adapter were very impressive. Also it could be configured with an enormous 640 K of memory, which was more than the floppy drive held.

For the record, all the popular small systems of the time had third party add-ons. That's a tradition that goes back all the way to the Altair. The Apple II didn't even have an RF modulator, because a third-party deal saved some headaches for Apple. All the systems came with full documentation. Apple even gave you the source code for the whole ROM in a separate manual right in the box, along with the schematics. Cloning the BIOS happened long after the PC had established its place - and the first clones had significant compatibility problems. Clones really didn't take off until Compac beat IBM to market with a 386-based machine.

Re:Thank Phoenix Technologies (1)

metamorphose (993342) | more than 7 years ago | (#15887478)

But but
Point 1 is making the same argument as point 2
Point 4 is simply what happens _after_ point 3, or simply the cause of point 3 - not seperate factor
In effect, you document 2 factors: the IBM name was useful in selling the things, and the machine had a large number of component suppliers due to full documentation of the hardware.

Re:Thank Phoenix Technologies (3, Interesting)

clickclickdrone (964164) | more than 7 years ago | (#15887697)

>Business people tended to view Apple computers and Commodore computers as toys.
I'm not convinced. Over here in the UK CBM Pets and Apple IIs were all over the business world. Heck, even huge multinational banks used Apple II's. I knew some poor guy who had to log credits in to an Apple II running a database by Stoneware.
Business magazines of that era were full of ads for Apple IIs and all the business software/hardware you could buy for them.
Early reviews of the PC were also very negative, most noting Apple had nothing to worry about.

Re:Thank Phoenix Technologies (2, Interesting)

speculatrix (678524) | more than 7 years ago | (#15887794)

2. The computer had the IBM label on it. These days, the IBM label does not carry the same cachet that the IBM name carried in the 1980s. At that time, IBM dominated the mindshare in the computer industry. People often said, "No one was ever fired for buying an IBM computer."

IBM's previous attempts at a home or personal/small-business were laughable. And the first PCs were pretty crap compared in features and performance - whilst the first 8088 or 8086 IBMs and compatibles struggled on with 80x25 character displays, a beeper and crude user interfaces, the Mac + Atari + Amiga people had bitmapped colour displays, digital audio and WIMP.

The only thing that made them interesting was the modularity and standard expansion slots; the rivals tended to be single-board devices which cost a lot more to expand.

It was only when the higher end 386DXs were around and bit-mapped displays that PCs even came close to rivalling the capabilities (hardware wise) of their rivals. It's a sad sad footnote in history that so much investment in time by both developers and third parties into Amiga, Atari & BeOS software has been "lost".

Re:Thank Phoenix Technologies (2, Interesting)

Waffle Iron (339739) | more than 7 years ago | (#15887863)

whilst the first 8088 or 8086 IBMs and compatibles struggled on with 80x25 character displays, a beeper and crude user interfaces, the Mac + Atari + Amiga people had bitmapped colour displays, digital audio and WIMP.

For business applications, after evaluating both those early color displays and the IBM monochrome text displays, most people would have chosen the the text display. For the time it was very crisp, with a nice font and special long-persistence phosphors. Early color displays (including IBM's) were fuzzy with garish colors. The IBM monochrome monitor (along with the outstanding keyboard) was designed to match the look and feel of their well-respected mainframe terminals. The WIMP GUI software of the time was too primitive to offer an improvement over well designed character mode apps for most business software.

When the PC came out, the Mac was still years in the future, and in comparison the Apple II and its ilk had poor ergonomics for someone trying to use the machine for serious work all day long.

First personal PC (2, Informative)

zymano (581466) | more than 7 years ago | (#15886988)

Was the 'blue box' Altair.

It inspired most of the techno-nerds from Gates to Jobs.

Re:First personal PC (1)

tinrobot (314936) | more than 7 years ago | (#15887133)

My first job ever was programming job costing apps for a company that had an Altair 8000b.

My first personal computer was a Honeywell 6000. (Actually Honeywell owned it, my dad worked for them developing Gecos & Multics -- we had a TTY in the den)

Altair & the Apple I (4, Interesting)

VValdo (10446) | more than 7 years ago | (#15887525)

Funny you should mention it. I was just reading this fascinating account [foundersatwork.com] by Steve Wozniak about how he invented the Apple I (semi-technical), and he talks a bit about the Altair.

Anyone have a "Woz" //gs?


Impact (1, Interesting)

treak007 (985345) | more than 7 years ago | (#15887010)

Looking back at the past, IBM was probably one of the most influential computer companies. Their Thinkpad notebook line was considered possibly the best notebook in existance. It's a shame that they were purchased by Lenovo, even if Lenovo continues making good Thinkpads.

Re:Impact (3, Interesting)

plover (150551) | more than 7 years ago | (#15887159)

Looking back at the past, IBM was probably one of the most influential computer companies.

"Probably"? :-) When I was in college, Apples were 'it' for the in-school computers -- IBM hadn't developed the 'PC' yet. We still had terminals and modems for accessing the CDC mainframe, but the Apples were there, and they were all yours. No sharing, no operators, just pop in your disc and go. It was an amazing machine.

I wanted to get one for home, but my dad told me we weren't going to buy an Apple. He was waiting for the IBM home computer to come out. He said "IBM doesn't do anything half-assed. If there's a business need for it, IBM will come along and completely dominate the market. Apple will be pushed aside; they'll never make it as the mainstream computer for businesses."

I, of course, couldn't believe that for a second. Every school in the state had Apples, they were everywhere, and this IBM thing didn't even exist! How could he even think that a company with no experience in home computers would take over the market, especially since Apple was so well entrenched?

Y'know, I wish I'd listened to my dad more. He was a very, very wise man.

Re:Impact (2, Insightful)

monoqlith (610041) | more than 7 years ago | (#15887319)

His conclusion was right but his premises were false. Apple made computers as well as or better than IBM. They just weren't as prescient on the business side. They failed to get a clue once they introduced the Macintosh, when it was time for both sides to lay down their chips. Microsoft, with Windows. Apple with the Macintosh Operating System. If Apple had chosen at that point to license its operating system we would be in a very different world today. I'm not sure that I would prefer that world, because chances are Apple would have become anti-competitive and monopolistic, and their product quality would have diminished. And Microsoft wouldn't have likely risen to be the resident industry source for R&D innovation like Apple has done in actuality.
    In a way, they continue to make the same mistakes - only this time, they're not mistakes. They are still controlling every aspect of the platform. However, they are positioning themselves in such a way that will result in a much higher-profile competition with Microsoft - a head to head battle, the same hardware platform with different software. If Apple ever overtakes Microsoft in market share (in the distant future, if at all) they are then in a position to start licensing their operating system, and they will have recreated the opportunity they completely missed in 1984.

Re:Impact (1)

monoqlith (610041) | more than 7 years ago | (#15887328)

Correction: Microsoft with DOS and then Windows, I mean. IBM really isn't a big player in the PC business anymore, so it's hard to say that they "won" at all - when they had their chance to crush Microsoft, they screwed it up too.

Does it run UBUNTU ? It must run UBUNTU !! (0)

Anonymous Coward | more than 7 years ago | (#15887024)

Does it run UBUNTU ? It must run UBUNTU !! or it is not a PC.

Re:Does it run UBUNTU ? It must run UBUNTU !! (4, Funny)

kongit (758125) | more than 7 years ago | (#15887128)

Sadly I couldn't get it too, wouldn't fit on a 5" floppy.

the x86 (5, Interesting)

phantomfive (622387) | more than 7 years ago | (#15887047)

On the one hand, the x86 is a terrible design. It doesn't have enough registers, and the assembly interface is awkward (especially in the FPU). On the other hand, the openness of the architecture has freed us from the shackles of dependency on a single company for hardware (which DRM would like to lay back on us). If you don't like Intel, you can go to AMD. There are tons of board manufacturers to choose from, and all the parts need to be (more or less) interoperable.

This prevents one manufacturer from imposing their wishes on us. If Microsoft had control of their personal computer platform the way apple does, we surely would have lost the battle to DRM already. Computers would be more expensive because there wouldn't be competition from cheap manufacturers in Taiwan to drive the prices down.

The x86 may be an ugly beast, but it gives us the freedom that only openness can bring. And I will drink to that.

I was always amused by this... (1)

hullabalucination (886901) | more than 7 years ago | (#15887136)

From Intel's website:

Starting from the highest to the lowest the IRQ priorities would be 2/9,10,11,12,15,3,4,5,6,7.

Well, that's kinda...logical...I guess.

* * * * * *

Clear? Huh! Why a four-year-old child could understand this report! Run out and find me a four-year-old child, I can't make head or tail of it.
--Groucho Marx as Rufus T. Firefly

Re:I was always amused by this... (3, Informative)

pe1chl (90186) | more than 7 years ago | (#15887654)

Well, in those days other chip manufacturers used a single interrupt line and either polling or vectoring. Priority was determined by the software or by a hardware daisy chain (e.g. in Zilog's vectoring system, which worked beautifully).

Intel used a special chip that was dedicated to interrupt vectoring, the 8259. It had 8 inputs of fixed priority, int 0 being the highest and int 7 being lowest.

The 5150 had one of these, and the ints 0 to 7 were partly hardwired and partly on the ISA bus.
A stupid design mistake was made: interrupts were edge-triggered on the 0->1 edge of the input. This was a programmable option in the 8259, which could also operate in a level-sensitive mode. This mistake meant that interrupt lines could not be shared between cards.
(other manufacturers of the time used active-low level-sensitive mode, which meant it was possible to share interrupt lines)

When the AT appeared, and the number of available lines was felt too limited, a second 8259 was connected to int 2 of the first, and its input were designated 8..15.
Input 9 was connected to the bus pin that originally was number 2. Hence the 2/9.
The priorities of inputs 8..15 became relative to int 2, thus the complete priority sequence becomes:


Some of those (0,1,8,13,14) are used on the motherboard. The remainder is on the ISA bus.

Later, when MCA and PCI were developed, engineers corrected their mistake and used level-sensitive interrupts that could be shared.
But in the name of backward compatability, the strange interrupt numbering and handling has always remained there.
(current systems have 24 levels and more freedom in programming the whole thing to the OS developer's liking)

Re:the x86 (3, Insightful)

evilviper (135110) | more than 7 years ago | (#15887235)

This prevents one manufacturer from imposing their wishes on us. If Microsoft had control of their personal computer platform the way apple does, we surely would have lost the battle to DRM already.

If the PC was as tightly controlled as Apple's platform was... You probably would not ever have heard of Microsoft.

Microsoft didn't make the PC, IBM did. They were just lucky enough to be in the right place at the right time, to ride the wave of "openness", which depended on their closed software for interoperability.

Re:the x86 (4, Insightful)

linguae (763922) | more than 7 years ago | (#15887266)

There are just a few problems:

The x86 has managed to kill off every other competing processor in the desktop space and relegate them to embedded computing or history books. First Alpha, then MIPS, and finally the PowerPC. (I'm typing this on an Intel Mac). We are now back to one architecture again, which is good for compatibility, but sucks for platform diversity. Not that I'm complaining about my computer (or the latest x86 offerings in general); you can't go wrong with the 1.83GHz Core Duo. The new Xeon chips make a dream machine. Intel did a very good job with the internals of the processor, by making it RISC-like (while still maintaining the x86 instruction set) and making it perform fast and relatively cool at the same time. I also like AMD's offerings; the Athlon 64 makes 64-bit computing very affordable (with great performance). But what about 10-20 years from now? Where will the new computer architecture ideas (or, more specifically, microprocessor ideas) come from? Will we finally get beyond the x86 instruction set? (Anybody who can point me to some recent academic/industrial research in this area will make me happy).

Secondly, guess who is in the Trusted Computing Group? Intel and AMD. My Intel Mac has a TPM chip used to make sure I don't do something like purchasing a $299 Dell special desktop and installing OS X on it. Most new Core Duo laptops sold have some sort of TPM chip on them, although as of yet they have no use (unless you have a Mac). Imagine what happens when the law/**AA/Microsoft/whatever demands hardware-enforced DRM. Well, we already have the hardware on the Intel machines. AMD probably doesn't want to lose a few sales and doesn't want to look out of date, so they'll implement a TPM chip, too. Since there are no other architectures to choose from, you're stuck.

Now, hopefully this doesn't happen. I am optimistic that this won't happen. There is quite a bit of backlash of DRM (even with normal consumers; look at the Sony rootkit fiasco, for example). However, it can happen, and the architecture for hardware-enforced DRM is falling into place. It's just the software that's falling behind, as usual.

Re:the x86 (1)

evilviper (135110) | more than 7 years ago | (#15887658)

We are now back to one architecture again, which is good for compatibility, but sucks for platform diversity.

Well, IBM's Power/PowerPC seems to be doing just fine, as are several handheld architectures (Arm, MIPS, SHx).

And, you're acting like a single common architecture is a bad thing. With the switch to x86-64, and other parallel advances, almost all of the benefits of the alternative architectures are gone. Who's to say that a common hardware platform is bad?

Where will the new computer architecture ideas (or, more specifically, microprocessor ideas) come from?

Well, since AMD came up with x86-64 in the first place, and Intel was pushing Itanium, I'd say they're likely to continue advancing the technology, without the need for other architectures competing.

Imagine what happens when the law/**AA/Microsoft/whatever demands hardware-enforced DRM.

Imagine what happens when the law impose prohibition on alcohol... We won't be able to find a drop.

Seriously though, whatever forces would drive Intel and AMD to require DRM, would surely have forced the same move on other propritary architectures as well. The ways to workaround DRM are exactly the same, no matter how many architectures there happen to be.

Re:the x86 (1)

Gordonjcp (186804) | more than 7 years ago | (#15887301)

If Microsoft had control of their personal computer platform the way apple does, we surely would have lost the battle to DRM already. Computers would be more expensive because there wouldn't be competition from cheap manufacturers in Taiwan to drive the prices down.

Ah, but if both the PC and Mac were locked-down single-manufacturer platforms, than another, more open platform would appear. Do you really think all those clever little Koreans would just sit on their arses and make nothing but MS-PC (for want of a better name) bits? You'd probably find something heavily Motorola-based would beast up the market. I still wish it would...

OTOH, assembler, board design was easy in X86 (4, Interesting)

Flying pig (925874) | more than 7 years ago | (#15887420)

In the late 70s/early 80s I worked with a number of 16 bit architectures - TMS9900, 8086, 68000, F101, PDP-11. The great thing about the X86 was that it was extremely easy to use for the migrating 8-bit programmer and it was easy to teach. Not so easy for me, I began on 16 bit and then in later years had to do embedded work with 8 bit processors which I hated!

In fact all the early processors had their architectural horrors. The 9900 had an absurd system in which the bit order of IO was reverse numbered with respect to the bus and we actually got an I/O board into production before we realised this owing to the poor documentation. The 68000 constantly caught out assembly programmers because of its word alignment issues, resulting in one occasion in a programmer going near berserk and having a screaming fit in the lab, fortunately when the boss was out at a meeting. And don't talk to me about the F100/L except to say that Ferranti did not get as much pain as they deserved for creating it. Not that it would ever have become mainstream...

It's easy to be clever with hindsight, but the Power architecture came later and too late. After, as I recall, the NS32032 which, despite some performance issues, was a processor I really liked.

Re:the x86 (1)

itdlev (205092) | more than 7 years ago | (#15887441)

However terribly designed, the open architecture has freed us from being locked down to a particular platform. That's the first thing that came to mind. But when I think of my first 80286 in the late 80s, it is the (relatively) cheap pricing that has the greatest impact me. If it wasn't for the cheap price tag back then, I wouldn't even get a computer in the first place. Forget about being locked down to a particular manufacturer.

Re:the x86 (3, Interesting)

nickos (91443) | more than 7 years ago | (#15887634)

Originally, IBM's engineers had wanted to use the much nicer Motorola 68000, but some of the business types at IBM had a deal with Intel so they went with the 8088 instead. I see no reason why things couldn't have developed differently with the 68k series being used instead of the x86 - the platform could still be open and other companies would still clone the 68k...

Re:the x86 (1)

pe1chl (90186) | more than 7 years ago | (#15887713)

The IBM PC was designed when desktop systems were still 8-bit. IBM wanted to design an 8-bit system, but certain people recommended to go for 16-bit, and a compromise was found in the 8088 that had a 16-bit architecture but an 8-bit bus. So the hardware could be built for 8 bits, and the software still could use 16 bits. This fell within the design criteria and cost objectives.

The 68000, on the other hand, was one step up. This was a 32-bit processor with a 16-bit external bus. Costs would certainly have been higher when using that.
An 8-bit external version (68008) appeared only later, probably when Motorola saw the success of the 8088.

In 1981, the 68000 was seen in "supermicro" systems, definately in a higher price class than the IBM PC. They were used as departmental computers with several terminals.
Use of the 68000 in desktop systems became popular in later years, but then IBM was already bound to Intel and used the 80286 in their AT.

68000 wasn't 32 bit, being picky (1)

Flying pig (925874) | more than 7 years ago | (#15887755)

As I recall it had a 16 bit ALU. As a result fixed point multiply and divide were bottlenecks. It had 32 bit data registers and address registers, but this does not make it a 32 bit microprocessor. (In the same way, the RCA 1800 series had 16 bit registers but an 8-bit ALU, and nobody would ever call that a 16 bit processor).

I know this is heresy, but IMHO the 68000 was actually a dead end, which is why it was ultimately abandoned by Apple. The 86 instruction set forced Intel to redesign the processor below the assembler level, the Power architecture was nice from the beginning, but the 68000 was neither one thing nor another. In comparative tests, our National Semi 32016 evaluation machine absolutely chewed a similarly specced Motorola workstation on a technical workload back in the 80s.

Re:68000 wasn't 32 bit, being picky (1)

pe1chl (90186) | more than 7 years ago | (#15887797)

At first I had included this note in my reply (the 68000 really being 16 bit) but I left it out for readability. But you are right about that.
However, to the programmer it appeared to be fully 32-bit and it could in later models be easily extended to be 32-bit without effect on software.
(compare that to the 386 which needed new software that used 32-bit opcodes)

Of course the main reason the 68000 became a dead end, is that it was not used in the PC and no development money went into it.
The 68000 could have been re-designed the same way the x86 was, but there was no money to be made so no reason to do it.

I don't want to defend the 68000 too much. I have used Atari ST machines for several years and I fully realize that although it looks beautiful at first, there are serious drawbacks, like:
- the two kinds of registers (D and A) are a nuisance
- the fixed opcode size means the cpu needs to read more opcode (program) data, consuming memory and bus bandwidth better left for data

It was generally seen as a bad PDP-11 copy.

Re:68000 wasn't 32 bit, being picky (2, Insightful)

nogginthenog (582552) | more than 7 years ago | (#15887989)

The 68000 didn't have fixed opcode size. The minimum was 2 bytes though. If you think 2 kinds of registers are a nuisance you should try programming on the x86!

Later 680x0 processors allowed you to use Dx registers as address registeres IIRC, but had a performance hit.

It was Compaq that opened up the clone market (4, Informative)

BadAnalogyGuy (945258) | more than 7 years ago | (#15887055)

The article gave pretty short shrift to the Compaq engineers for the reverse engineering of the PC architecture.

Imagine you were Chinese and had laid bare before you the innards of some cool technology that until now was locked up tight. You'd be the first one to put down your eggroll and cat-kabob and get right to the task of extracting its secrets. That's when you'd open up the clone market. It wouldn't be the prerogative of the original company whether you created the clone or not, it's out of their hands once they decided to use an open architecture.

Compaq blazed the clone trail, not IBM.

Mod parent up (1)

i.of.the.storm (907783) | more than 7 years ago | (#15887094)

Very good point. Without Compaq, we would be nowhere today, but I guess without IBM there would be nothing to reverse engineer.

No, Columbia Data Systems was first (4, Interesting)

Terje Mathisen (128806) | more than 7 years ago | (#15887144)

Just after the PC introduction (at NCC fall 1981) I told my father-in-law that we should re-implement the software used for OCR processing in his downtown office. We should select something PC-compatible since this new open architecture was bound to generate compatibles, thereby ensuring a pretty long lifetime.

After looking around the market, we bought two Columbia PCs, one desktop (with an immense, never to be filled, 10 MB hard drive) and one luggable, for the same price as a single IBM PC.

The Columbia machine came with a BIOS/HW manual that documented all the various lowlevel interfaces, including the port adresses for things like the serial port and the interrupt controller, which allowed me to write a hw interrupt driver for the incoming 9600 baud OCR data stream.

Columbia was both earlier than Compaq and more compatible, but that didn't matter, they still went under a couple of years later. The PCs lived for many years however. :-)


Re:It was Compaq that opened up the clone market (1)

the_humeister (922869) | more than 7 years ago | (#15887162)

Yes, cat. The other white meat.

Waaay OT, but.... (0)

Anonymous Coward | more than 7 years ago | (#15887364)

I don't know whether or not it counts as white meat, but I believe they refer to cat and dog as "perfumed" or "fragrant" meat. However, from what I've heard, that moniker is something of a generous euphemism.

Re:It was Compaq that opened up the clone market (1)

Stormwatch (703920) | more than 7 years ago | (#15887173)

Compaq reverse-engineered IBM's BIOS, and wrote their own. Result: Compaq made PC-clones.

Not too long after that, Phoenix Technologies reverse-engineered IBM's BIOS, wrote their own, and licensed it. Result: tons of companies made PC-clones.

Re:It was Compaq that opened up the clone market (1)

ClosedSource (238333) | more than 7 years ago | (#15887251)

But all that reverse engineering would have come to naught if IBM hadn't chosen an outside company to provide the OS and that company hadn't pushed for the right to sell the OS to others. MS also played a key role in making the multiple-vendor PC market possible.

Acorn (1)

RealGrouchy (943109) | more than 7 years ago | (#15887097)

Is it just a coincidence that the codename for this project was Acorn, or was the use of the codename in Dilbert a deliberate homage? (sorry, can't find video reference)

- RG>

Re:Acorn (0)

Anonymous Coward | more than 7 years ago | (#15887146)

Yes, the use in Dilbert was a deliberate homage. It takes a true techno-geek to get ALL the references packed into Dilbert, which is why it's so good.

No! (0)

Anonymous Coward | more than 7 years ago | (#15887122)

IBM PC didn't change the world. Taiwanese clone PC changed the world. They made computing accessible to the mass.

What? (1, Funny)

Anonymous Coward | more than 7 years ago | (#15887135)

Haven't you heard? Apple is responsible for everything innovative and great. I can link to a picture gallery of mac users with Apple logos branded and dyed-black hair to prove it.

Ah, the 5-slot PC... (1)

MsGeek (162936) | more than 7 years ago | (#15887140)

My first computer. Of course, mine was gotten in 1987, when the 386 was common and the 486 was t3h 1337 b0xx. Castoff from my uncle's CPA practice. One hell of a little machine.

Re:Ah, the 5-slot PC... (1)

7grain (583823) | more than 7 years ago | (#15887491)

Agreed. Totally durable. My folks bought an 8088 PC in 1981. I was 12. 4.77 mhz, woo hoo! Ten years later, I STILL had it in my senior year of college (they had upgraded to an Epson 286). Along the way, I had upgraded from the base 64 KB of ram to 448 KB, and added a 10 MB hard drive. It had originally shipped with 2 5 1/2" 360kb full-height floppies, of course. Half of the hard drive contained the installation of Word Perfect 5.1 (about 5 MB.) The other 5 MB had, um... Procomm Plus... Tetris... Lotus 1-2-3 (v2.1) and a lot of data files.

The 286, 386, and 486 generations had been introduced by the time I put that sucker to rest. but not before I'd become completely hooked on computers and everything about 'em. Damn, it ruined me for life! :-)

Crock of shit. (0)

Anonymous Coward | more than 7 years ago | (#15887167)

Commodore et al were the drivers of the personal computing industry. IBM jumped on board with a me-too but the platform didn't achieve sales that compared to Commodore, Radioshack, Tandy, Apple or Sinclair until well after those platforms were eclipsed.

MSDOS PC's only became the plaform of choice because of DOOM.

I have one of those... (0)

Anonymous Coward | more than 7 years ago | (#15887184)

in my closet

What if... (0)

Anonymous Coward | more than 7 years ago | (#15887226)

If IBM didn't do it, then someone else would have.

Last one I saw was in 1995 (2, Interesting)

marked23 (693822) | more than 7 years ago | (#15887242)

I retired a 5150 in 1995. It had a hard drive and maybe 128k. We used it every day. It was the computer we all used to store our CNC programs on. Connected to a serial port switch box running 100's of feet of cable to the CNC machines. It worked until the day we turned it off and replaced it with a contemporary Pentium. That was the last time I saw a 5150 in working order.

Re:Last one I saw was in 1995 (2, Interesting)

pe1chl (90186) | more than 7 years ago | (#15887580)

That is more likely to have been a 5160. The 5150 did not come with a harddisk. It was usually seen with two floppies, but it even had a cassette recorder interface.
The memory often was only 32 or 64K.
The 5160 (IBM PC XT) followed shortly after the 5150 and had a whopping 10MB Harddisk, 8 instead of 5 slots, no cassette interface, and some more memory by default.

Somewhere in 1983 (maybe early 84) we got one of those in the office, fully populated with memory (640K) and running XENIX.
It was used as a low-end platform for our Unix-based application that usually ran on larger systems like the NCR TOWER or a PC-like box from Fortune Systems.

Indeed, they were reliable. I think that is one of the major contributions of IBM into the Microcomputer world. Until then, there were systems from names like Commodore, Radio Shack and Apple that really were hobby systems and had lots of glitches. IBM introduced a sturdy system (although expensive) that you could put in a workshop or professional office without worrying about it breaking down all the time, or looking like a toy.

Re:Last one I saw was in 1995 (1)

Goat Nutrition (720344) | more than 7 years ago | (#15887811)

We had one of the very early IBMs in the UK, in (I think) early 1982, and it did have the tape cassette interface for saving programs (perfectly normal for PCs of the time) - although we were much more excited that it had ** a floppy disk drive **. Sigh.

The turnaround of IBM (4, Interesting)

iota (527) | more than 7 years ago | (#15887246)

What the IBM 5100 really represents, in retrospect, is the beginning of the turnaround for IBM in the minds of the public. It's difficult to think of another example of a company so large and so universally despised eventually becoming the (mostly) developer friendly company it is today.

By allowing their teams to skirt the system occasionally, we've seen truly open hardware (PowerPC) availablity, open source contributions, free training seminars for developers, etc. The 5100 was the first great example of the success that a little rule-breaking can bring to the company.

IMO, it was exactly that product and the example that it was to IBM internally that allowed IBM to do the one thing no one was entirely sure it would be able to do in the age of personal computers -- survive.

My hat's off to the improvements IBM has made in the last 25 years, and I hope that those lessons won't be forgotten over the next 25 years.

Ummmm... (1)

KeithLDick (984953) | more than 7 years ago | (#15887296)

I think the Apple Computer had already done this... IBM may have kinda made it Personal but it had already been done...

At IBM WebSite say that it born at September 1981 (2, Informative)

corretge (994622) | more than 7 years ago | (#15887407)

In the IBM Site http://www-03.ibm.com/ibm/history/exhibits/pc25/pc 25_intro.html [ibm.com] reffers that IBM PC 5150 was released on September 1981.

IBM WebSite say that it born on August 12. (1)

systems_joe (873447) | more than 7 years ago | (#15887700)

That site clearly states that the Press Release occured on August 12, 1981. http://www-03.ibm.com/ibm/history/exhibits/pc25/pc 25_press.html [ibm.com] and http://www-03.ibm.com/ibm/history/exhibits/pc25/pc 25_birth.html [ibm.com]
On August 12, 1981, at a press conference at the Waldorf Astoria ballroom in New York City, Estridge announced the IBM Personal Computer with a price tag of $1,565.

The article misses important details. . . (0)

Anonymous Coward | more than 7 years ago | (#15887444)

. . . so I will happily comply in adding them to the story:

From VERIFIED sources:
QDOS, the "Quick and Dirty Operating System," was purchased in July 1981, a month before the PC's release, by Micro-Soft (Microsoft) for $50,000. QDOS was called "Quick and Dirty" since it was basically stolen from Digital Research by Seattle Computer Products (SCP). Bill Gates bought SCP after he sold the DOS code to IBM. When the code was presented to IBM by Micro-Soft, the IBM software engineers found over 1000 bugs. The IBM engineers corrected the bugs for PC-DOS.

From unVERIFIED sources:
According to many sources, including former Microsoft employees, the bugs IBM took out were forced to remain in Microsoft's version of the OS, MS-DOS. Microsoft took advantage of these bugs to put companies such as Digital Research, WordPerfect, Lotus and others out of business by not disclosing the bugs to its competitors.

Those leftover bugs now form most of the code base of Microsoft's latest operating system, named Windows Vista.

Re:The article misses important details. . . (4, Interesting)

ewhac (5844) | more than 7 years ago | (#15887527)

According to many sources, including former Microsoft employees, the bugs IBM took out were forced to remain in Microsoft's version of the OS, MS-DOS. Microsoft took advantage of these bugs to put companies such as Digital Research, WordPerfect, Lotus and others out of business by not disclosing the bugs to its competitors.

Actually, had PC clones not emerged, Microsoft would have been relegated to the scrapheap of history as just another vendor of a BASIC interpreter. And a fairly crappy BASIC at that.

However, once the clones emerged, MS had it made. IBM was certainly not prepared to put in the engineering work to make PC-DOS run on non-IBM hardware. Microsoft, however, was willing to do that work (or at least let PC OEMs pay Microsoft to teach them how to do it themselves), and offer pack-in deals. As such, IBM PCs came bundled with PC-DOS, and every other machine came bundled with MS-DOS.

Back then, just about everyone in the engineering community knew MS-DOS was shit, and would steer anyone who would listen toward PC-DOS, or Digital Research's CP/M-86 or Concurrent CP/M. However, most end-users considered MS-DOS to be "good enough," and it was "free," and they wanted to be able to run the same software they used on the real IBM PC at work on their cheap(er) clone at home. And besides any bugs were the application's fault.

Oh, and you're also forgetting what the gold standard of PC compatibility was at the time:

Microsoft Flight Simulator.

Amazing foresight? Maybe, to some degree. But in large measure Gates fell flat on his face into a pile of amazingly good luck.


Re:The article misses important details. . . (1)

Saffaya (702234) | more than 7 years ago | (#15887586)


Umh .. No.

It was SUBLOGIC's Flight Simulator II that was the well-know and ubiquitous metric.
And it was also perfectly ported to other architectures like the Apple II or the ATARI 800 XL.

Re:The article misses important details. . . (3, Insightful)

$RANDOMLUSER (804576) | more than 7 years ago | (#15887962)

While it's true that Microsoft Flight Simulator (NOT Sublogic) was the compatability standard mentioned in every review, the thing that sold all those PCs and all those copies of PC/MS-DOS was Lotus 123. 123 made the PC the way VisiCalc made the Apple II. Because Lotus wrote directly to the video memory, "sorta" clones (DEC Rainbow anyone?) that had BIOS, but not physical compatability, had no chance.

They Don't Make 'Em Like That Anymore (4, Funny)

Vollernurd (232458) | more than 7 years ago | (#15887504)

Man, the hardware... Hewn from a single piece of purest iron those things were (literally?) bullet-proof. The keyboards would last for years before even one of those keys stopped working.

Of course, you couldn't lift them. But whilst machines now whirr away at insane speeds and generally work well their keyboards suck.

Er... that's it. Just got misty-eyed there for a second.

Pure Fe is brittle (0)

Anonymous Coward | more than 7 years ago | (#15887618)

Pure iron is actually quite brittle. Cracks too easily to survive a drop or a bullet.

Re:They Don't Make keyboards Like That Anymore (2, Funny)

cdn-programmer (468978) | more than 7 years ago | (#15887640)

This is why I use an IBM keyboard which is over 10 years old on my present machine. The short of it is if the computer will not run this keyboard then I won't buy it or use it.

Re:They Don't Make 'Em Like That Anymore (1)

pe1chl (90186) | more than 7 years ago | (#15887676)

Actually, the keyboard of the original 5150 was subject of a lot of critisism!
Reviewers did not like the layout *at all*. For example, the swapped positions of Ctrl and Caps Lock, and the introduction of the Alt key and the strange form of Enter and the numeric keypad (combined with cursor arrows) really put them off.

The keyboards of the later AT and PS/2 systems corrected that. IMHO the early PS/2 keyboard is the best of all.

personal computing (1)

rubycodez (864176) | more than 7 years ago | (#15887511)

personal computing had been going strong since the mid 70's, I don't understand why everyone fusses about the IBM PC. I'd been into the hobby for four years already when that thing came out.

Re:personal computing (2, Insightful)

pe1chl (90186) | more than 7 years ago | (#15887667)

The fuss was about a computer that could be used in a business, vs the hobby computers that were popular before that.
Most of the hobby computers could not stand up to professional daily use, and the IBM PC could.
Personal computing went from hobby computing to being a business tool.

Involuntary psychiatric hold (1)

mverwijs (815917) | more than 7 years ago | (#15887630)

5150!??! But that's *insane* [1]!

5150 criteria

The criteria for writing a 5150 includes danger to self, danger to others, and/or grave disability - as noted below. The conditions must exist under the context of a mental illness and the person must be refusing psychiatric treatment.

  1. Danger to self - the person must be an immediate threat to themselves, usually by being suicidal. Someone who is severely depressed and wishes to die would fall under this category.
  2. Danger to others - the person must be an immediate threat to someone else. A person hearing voices telling them to kill someone would fall under this category.
  3. Gravely disabled, Adult - the person (over 18 years old) is unable to provide for their food, clothing, and/or shelter - and there is no indication that anyone is willing or able to assist them in procuring these needs. This does not necessarily mean homeless, as a homeless person who is able to seek housing (even in a temporary shelter) when weather demands it would not fall under this category.
  4. Gravely disabled, Minor - the person (under 18 years old) is unable to provide for their food, clothing, and/or shelter - even if these are supplied directly.

[1] http://en.wikipedia.org/wiki/5150_(Involuntary_psy chiatric_hold) [wikipedia.org]

Maths Co-Pro (2, Funny)

clickclickdrone (964164) | more than 7 years ago | (#15887681)

We're spoiled. I remember a friend enthusing that his firm had just fitted Maths CoPros to their XTs (I think) and that they could now refresh big AutoCad drawings in mere minutes.

Low End Mac, IBM, evangelists, etc. (1)

wysiwia (932559) | more than 7 years ago | (#15887711)

It's amazing what's written on the net. I always used LowEndMac for information about low end Macs and liked it very much. Yet does this story mean LowEndMac wants to switch to provide information about low end PCs after Apple switched to Intel processors?

Yet this story raises many other questions. How does IBM feel being famous for the most used kind of desktop processors but not being able to participate in that business anymore? How does Sony feel now its long time partner in several technologies (Apple) doesn't use the same processor (PowerPC Cell processor) anymore? How does Intel feel now Microsoft switched to PowerPC processors for their Xbox? Curious world these days, what can we expect next?

But what interests me most is how evangelists feel after so many changes.

O. Wyss

Why all PC clones had two Power Supply connections (2, Interesting)

sirwired (27582) | more than 7 years ago | (#15887748)

Did you ever wonder why ALL XT/AT motherboards in standard form factors had two power supply connectors? Especially since they were not keyed? (swapping the two could easily blow your motherboard.) I have heard that when IBM was preparing to ship the 5150, the supplier of power supply connectors (it happened to be Molex at the time) was out of stock of the 12? pin connectors necessary to integrate the whole PS connection into one. After that, every single PC Power Supply for many years shipped with two connectors on the output, because it had always been done that way.

Probably a crazy urban geek legend, but a cute story nonetheless.


Re:Why all PC clones had two Power Supply connecti (-1, Redundant)

Anonymous Coward | more than 7 years ago | (#15887877)

Actually - one was power INPUT. The other was power OUTPUT - so you could plug your monitor into the PC for power, saving a power point.

The great PC 'What if' (1)

owlman17 (871857) | more than 7 years ago | (#15887786)

This is a nice article that explores how the PC industry might have turned out if Microsoft never came to power as we know it in this world.

For alt-history buffs: "Now, here's an interesting question that looks back 25 years: What if IBM demands an exclusive license to that operating system? One of two things happens: Microsoft and IBM don't get a deal done, or Microsoft caves. Let's follow both scenarios as far as they can go:"

http://news.com.com/The+great+PC+what-if/2010-1042 _3-6102503.html?tag=fd_carsl [com.com]
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