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DDR4 May Replace Mobile Memory For Less

Soulskill posted more than 2 years ago | from the not-dance-dance-revolution dept.

Hardware 145

Lucas123 writes "The upcoming shift from Double Data Rate 3 (DDR3) RAM to its successor, DDR4, will herald a significant boost in both memory performance and capacity for data center hardware and consumer products alike. Because of the greater density, 2X performance and lower cost, the upcoming specification and products will for the first time mean DDR may be used in mobile devices instead of LPDDR. Today, mobile devices use low-power DDR (LPDDR) memory, the current iteration of which uses 1.2v of power. While the next generation of mobile memory, LPDDR3, will further reduce that power consumption (probably by 35% to 40%), it will also likely cost 40% more than DDR4 memory."

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Excellent (3, Funny)

DWMorse (1816016) | more than 2 years ago | (#40012619)

With RAM that fast and cheap, 640kB ought to be enough for anyone!

Whoops, I mean 6.40 x 10^7 kB. THAT ought to do it.

Re:Excellent (3, Insightful)

arth1 (260657) | more than 2 years ago | (#40012687)

Fast and cheap are well enough, but cool and reliable are important factors too.

From TFS, it looks like it may run cool, but I'll wait with the hallelujah until I've seen something about reliability. Especially because with die shrinks for flash, reliability has gone way down from the last generation - I hope that won't be the case with RAM too.

DRAM Cell Area (2)

Taco Cowboy (5327) | more than 2 years ago | (#40012977)

With Micron purchasing Elpida, Micron gonna get to make DDR4 DRAM with cell area of 4F2.

On the other hand, Samsung's DRAM is still occupying cell area of 6F2.

Re:Excellent (2)

iamhassi (659463) | more than 2 years ago | (#40013269)

Reliability is the reason I havent gone SSD yet. Every time I'm about to upgrade I read the reviews on newegg of some guy losing all his data. Guess if it's only for the OS and you clone it nightly that's not a big deal.... actually, that's not a bad idea, a small cheap ssd for the OS so it boots fast, then keep files on reliable hd and make clone of ssd to backup drive so u can still boot if the ssd dies....

Re:Excellent (0)

Anonymous Coward | more than 2 years ago | (#40013583)

Reliability is the reason I havent gone SSD yet. Every time I'm about to upgrade I read the reviews on newegg of some guy losing all his data.

I have used an SSD for my windows box for about 2 years now without problems. Meanwhile 2 younger spinning platter disks have died on me (No problem, I had backup on all important data.) and co-workers have had a couple of spinning disks die on them where one of them didn't have backup.

If you are worried you should try an SSD as a system disk, you can always re-install if it breaks.
Personally I am more worried about the spinning disks breaking down on me, all problems I have heard about SSDs were firmware problems that have been fixed. (Well, one of the spinning disks had that problem too.)
The problem with mechanical wear on spinning disks and their sensitivity for vibrations fells like a larger problem, but then again, I'm not that worried since I have backups.

Re:Excellent (1)

kyrio (1091003) | more than 2 years ago | (#40013713)

I've been using my 10k RPM Raptor for over 8 years now. All tests show that it's still in perfect condition.

Re:Excellent (1)

AvitarX (172628) | more than 2 years ago | (#40013587)

That's what I did for my htpc (I Wanted to keep the inside as solid state as possible, as It's so small).

I use a pair of 2.5 inch USB drives for reliability, and lack of cords for /home and backup.

Re:Excellent (4, Insightful)

TheRaven64 (641858) | more than 2 years ago | (#40013961)

Reliability is the reason I havent gone SSD yet. Every time I'm about to upgrade I read the reviews on newegg of some guy losing all his data

If 'some guy losing all of his data' is your reason for not buying an SSD, does it also stop you from buying a hard disk?

Ya no shit (5, Insightful)

Sycraft-fu (314770) | more than 2 years ago | (#40014211)

Also there's the fact that the people who post things like that are the whiny ones who had problems. I've never posted my SSD experiences before, because I'm happy, but here they are:

I have 3 256GB SSDs, one in my laptop, two in my desktop. All have worked without flaw since their purchase 11 months ago. Thus I never felt the need to go whine online about them. I've suffered no failures, no data loss. They just work.

Now, do SSDs die? Sure. So do HDDs. In terms of personal HDDs I've had about 5 fail on me over the course of my 20ish years using computers. At work, I've seen hundreds fail. Some are dead on arrival, some fail within hours of install, some fail after months or a year, some are still going strong 10+ years later.

SSDs are fine. You need to back up your data, but then that is true of anything. If you don't back up your data and have never lost anything to HDD failure that is luck, not because HDDs don't fail.

If you want an SSD the only issue should be cost. They are expensive, about $1/GB at best and as much as $3/GB for some of the really high performance/lots of write cycles stuff. HDDs are more like $0.08/GB. However if the price is acceptable, then get one. Back up the data on it to a HDD (since HDDs are cheaper, and a different technology) and you are fine. Could it die? Sure, if it does, RMA it, get a new one, and go back to what you were doing.

Re: never RMA a hard drive (0)

Anonymous Coward | more than 2 years ago | (#40014303)

never RMA a faulty hard drive.

They can send me a new one, but they're not getting the platters back unless they want platter dust. Period.

Re:Excellent (1)

rrohbeck (944847) | more than 2 years ago | (#40013363)

That's why there is ECC.
Why anybody runs without it is beyond me.
With EDAC I see occasional ECC errors on many systems.

Re:Excellent (0)

Anonymous Coward | more than 2 years ago | (#40013671)

Why anybody runs without it [ECC] is beyond me.

Combination of cost (ECC costs more, partly because it's used less, partly because it needs more RAM chips), availability (fewer places carry it), and support (Intel only allows it on Xeon systems; AMD supports it on all their chips, but only a few motherboards will take it - and they tend to be the more expensive ones.)

I agree, mind you - this is one of the reasons (not the only one) I sprung for a Mac Pro shortly after their last refresh - but parity (and ECC) RAM is dead in the general consumer market. Blame the almighty buck.

Re:Excellent (0)

Anonymous Coward | more than 2 years ago | (#40013607)

I wish this meme would die. The part of that which you're forgetting is that it refers to the way that they opted to split the 1MB of RAM that they were working with. And 640kb at that time was indeed enough for anybody since they couldn't use the entire 1MB in one piece.

And it was never intended to apply to the future, nobody at that point dealing with computers would be foolish enough to say that they would never need more than 640kb as at that point they had already created computers with more than that.

Re:Excellent (1)

Anonymous Coward | more than 2 years ago | (#40013721)

your source is missing. but i guess it's hard to hyperlink your asshole.

Re:Excellent (1)

Anne Thwacks (531696) | more than 2 years ago | (#40013759)

The real point is that, at the time he said it, even Bill Gates could only afford 64k. Most Minicomputers only had 32k address space, and the idea that anyone could actually afford 640k was laughable.

Re:Excellent (3, Informative)

TheRaven64 (641858) | more than 2 years ago | (#40013981)

I've found it interesting how this has been repeated and justified in so many ways over the years. The first time I heard this quote was the mid '80s, and it was '64KB ought to be enough for anyone', not 640KB. Back then, it was apparently related to a hard-coded limit in Microsoft BASIC, which limited it to 8-bit computers. The alleged context was that this was Bill Gates' facetious reply when asked about this limit with regards to the new 16-bit microcomputers. As I recall, early versions of Microsoft BASIC on the IBM PC only supported 64KB, even though the machine could address ten times as much.

Re:Excellent (2)

jd (1658) | more than 2 years ago | (#40014157)

Sir Clive Sinclair gave very similar reasons for using the 68008 (the 8-bit version of the 32-bit 68000) - he stated that nobody needed a 32-bit computer, but that you needed a machine to be advertisable as a 32-bit system to compete with the Mac and Atari ST.

Re:Excellent (2)

jd (1658) | more than 2 years ago | (#40014143)

Actually, they could. The processors of the time used two interwoven 16-bit registers with a 12-bit overlap. (This meant some memory locations had multiple addresses.) The total sort-of-linear address space was therefore 20 bits, or 1 megabyte.

Plenty of extended memory cards existed at the time, which used a memory banking system to produce the illusion of larger machines. The only restriction with banked memory is that it slows the machine down as the CPU can only see one bank at a time. Well, that and reads/writes can't span multiple banks.

Yay (0)

Anonymous Coward | more than 2 years ago | (#40012629)

I can't wait until my iPhone 4 is yet another generation behind, and every other phone is better than mine... Then I will laugh at my colleagues who spend $200 on a phone when mine still does more than I need...

Re:Yay (5, Insightful)

Anonymous Coward | more than 2 years ago | (#40012657)

mine still does more than I need...

I gave up talking about "need" when it comes to mobile phones long ago. It is really about "want" (for all but a very few folks who have a real need for work - most who think they "need" it for work, don't). It took me awhile to move from an old dumb phone to a smart phone. But I was finally honest with myself - and damn it I wanted one. I got one and was thrilled with all the things I can do with it. I still wholeheartedly consider smart phones a luxury - but I am glad I can afford one and finally talked myself into parting with the money and monthly payment for a data plan (I'm sort of a cheapskate). The whole family of four has them now, three of us on our second generation of them.

Go ahead and laugh. Your phone does more than I need too. But it doesn't do more than what I want.

Re:Yay (0)

Anonymous Coward | more than 2 years ago | (#40013067)

Pretty much the same calculation I made a few months ago.

When I ran across Ting though, I couldn't resist. I figured I'd be happy with a cheap Android (and I am). The phones we got (Otimus S - yep, bottom of the barrel) are (now) $170 each (plus tax and shipping but "activation" is included).

The base charge is $6/line for service. Then you pay for the "bucketized" usage of a pool shared among all your devices (<=100 minutes is $3/month; <=100 MB is $3/month; <=100 txt msgs is $3/month -- if you use zero of any category I think you pay nothing).

Primary service is on Sprint. Data and Text roam at no charge to Verizon (that's hard to beat). Data roaming is not offered and data coverage is not as good as going with native Sprint because native Sprint seems to have data roaming agreements that Ting does not seem to share (check coverage maps @ Ting carefully for data).

So, for two smart phones we paid less than $400 up front and pay as little as $25/month (taxes/fees included) if we use a little, but not much, voice, text, and data.

It's great if the limitations fit your needs.

(You can save $25 on your first device by following a referral link -- but, unfortunately, I won't give mine here because it exposes my name to those who follow it.)

Re:Yay (1)

kyrio (1091003) | more than 2 years ago | (#40013729)

My Android phone was $70. It does all the things. I pay $17/m for unlimited call and text and maybe other things, I don't know. I barely use the call and text, anyway.

Re:Yay (1)

BradleyUffner (103496) | more than 2 years ago | (#40012663)

And people with "normal" phones will continue to laugh at you because they spend $50 on a phone that does more than /they/ need...
People have different needs.

Re:Yay (1)

beckerist (985855) | more than 2 years ago | (#40012847)

... shit's gettin' smaller son...deal with it

Re:Yay (1)

beckerist (985855) | more than 2 years ago | (#40012853)

p.s that was both pedantic and shallow....and also a smidge of sarcasm

there's only two needs (0)

Anonymous Coward | more than 2 years ago | (#40012911)

air and sustenance. i can verify with fact everything else is just a want

Re:there's only two needs (1)

dougisfunny (1200171) | more than 2 years ago | (#40013263)

I imagine someone could synthesize some sort of gel which would transport oxygen and 'breath' that instead of air. But that's just getting pedantic.

Re:Yay (0)

Anonymous Coward | more than 2 years ago | (#40014229)

Meh, you'll mostly be laughing because they'll have steam-packed some Samsung XXXS Arousal with lots of DDR4 (instead of LPDDR3), a huge screen, specs through the roof, and an impressive 4h of battery life.

Awesome. (4, Insightful)

bistromath007 (1253428) | more than 2 years ago | (#40012651)

Now we just have to wait for Intel to give a goddamn about it. Quick, somebody tell AMD to be competitive again for a few months.

Re:Awesome. (3, Interesting)

Baloroth (2370816) | more than 2 years ago | (#40012703)

If DDR4 is really as power-saving as they say, AMD will be competitive simply by adapting it (more than they already are). At the low-power end, especially low-cost low-power, AMD is pretty competitive with Intel already. If they can push out server DDR4 compatible products first, they could stand to gain quite a lot (Intel isn't planning on offering DDR4 till 2014, so AMD has a year and a half).

Re:Awesome. (1)

rrohbeck (944847) | more than 2 years ago | (#40013381)

Mmmm, 4 way DDR4 - I'd buy a new motherboard for that.

Re:Awesome. (2)

TheEyes (1686556) | more than 2 years ago | (#40013383)

Even more interesting is that AMD's APUs are severely memory-constrained; even Llano really needed DDR-1866 or higher (if it existed) to really show what it could do, and Trinity is probably even more constrained. If AMD goes the same route as they did with Phenom II and includes both a DDR3 and DDR4 controller (and makes their chip compatible with both old sockets and new DDR4-compatible ones) they might be able to pull off some interesting design wins in the low power gaming-capable market.

Re:Awesome. (2)

hairyfeet (841228) | more than 2 years ago | (#40013569)

But gamers are, for the most part, gonna use a discrete rather than an APU and the consumers frankly don't know DDR 4 from a grilled cheese sandwich so other than a few benches I just don't see it making that big a deal. Sure the higher scores will make a nice bullet point but I have one of the E350 APUs and with 1200Mb of DDR 3 1333MHz RAM dedicated to video movies are buttery smooth and the games I play don't jerk and isn't that what matters?

I've been selling AMDs in my shop pretty exclusively since the Intel bribery and compiler scandals came out and while i thought killing AM3 was a stupid move frankly i haven't had ANY trouble selling the APUs and the reason couldn't be more simple. The simple fact is just about every APU that AMD has, even the lowly C and E series bobcats are frankly overkill for most of the jobs folks have. Hell I even sold my 17 inch laptop for one of the 12 inch AMD EEEs because i found when i'm mobile i liked having the battery life and ease of carry over the big screen and you know what? i honestly don't miss that more powerful CPU.

So while i'm sure the extra speed will do nothing but help AMD I just don't see what DDR speeds they have now hurting AMD with actual consumers. BTW for those that have C and E series APUs I recommend Brazos Tweaker [google.com] which will help you drop voltages and get even greater battery life. they have settings that will work on most of the C and E series posted as well as step by step instructions. I added about an hour to mine by using it and honestly I can't "feel" any difference in performance, I just get more time.

Re:Awesome. (1)

jd (1658) | more than 2 years ago | (#40014185)

AMD has now low-power cores due out later in the year. I imagine their timing is designed to make it possible to have manufacturers design motherboards with the new memory in mind, rather than have them aim for DDR3 and only develop a DDR4 board later.

Re:Awesome. (3, Interesting)

hairyfeet (841228) | more than 2 years ago | (#40013483)

Ya know I just have to laugh at statements like yours because while the reviewers haven't liked AMD that hasn't stopped the OEMs from gobbling up every chip they can handle. hell AMD had to slow down their desktop lines just to give more room to mobile because they kept running out! Take the Bobcats, they haven't had an update in awhile yet the OEMs are slapping them into everything from netbooks to laptops to all-in-ones as fast as they can get them, same with llano. Even the lower end Bulldozers have been selling quite briskly and the reviewers couldn't stand that chip!

What thing AMD does seem to get is to coin a phrase "Its the GPU stupid". I mean what does the average person DO with their machine? FB, webmail, YouTube videos and movies. Is there a single job on that list that even the lowest bobcat can't do? Nope. Hell I recommended to my dad to get his GF a little Acer with the C60 chip in it which is just a 1Ghz dual core with turbo and she can't stop gushing about the thing! it plays her FB games, let's her chat anywhere without being tied to the cords, she is just tickled to death with it.

While DDR 4 may give the integrated GPUs in AMD chips a little speed boost frankly they haven't been having too much trouble selling them or having them run pretty much anything you want. Don't take my word for it, look up the Youtube videos on chips like the E350 where they are playing Crysis on it. I have 8Gb of DDR 3 in mine which gives the GPU 1200Mb of system memory and while i don't often game on it i can say that the little E350 stays cool to the touch even after hours of HD video or office work.

So I don't think you have to worry about AMD friend, once they have gotten rid of the last of their stake in GloFlo they should be doing quite well with Piledriver and Bobcat II. The RAM in TFA will give it a free speed boost but the only ones who seem to care about such things are the reviewers. For everybody else as long as it does the tasks they have with good battery life they'll be quite happy.

Re:Awesome. (2)

dbIII (701233) | more than 2 years ago | (#40014011)

They are VERY competive in some markets:
64 core 2GHz AMD system 128GB memory - $9000
80 core 2GHz Intel system 128GB memory - $66000
There may be some Intel systems around the 60 core mark (six sockets, ten cores), but I've got no idea how much it would be and it would still max out at 2GHz for now. To get speed you've got to go for less cores :(

You really think it is so easy? (3, Informative)

Sycraft-fu (314770) | more than 2 years ago | (#40014167)

You think all Intel has to do is say "Hey! We'd like to support DDR4," and it just happens?

Not so much, actually. First off it has to actually, you know, be a real specification. The spec isn't final and released yet. They can't really start to use something that isn't final and subject to change.

Once it is actually out comes the harder part. They have to redesign the memory controller, which is on the chip now, to accommodate it. DDR4 isn't "DDR3 but faster," it is a different spec that works differently. Big different is no more RAM channels with multi-sticks. It is a point-to-point memory interface. So that is going to require a different setup, particularly to support large numbers of memory sticks. Also along with that the motherboards will have to be redesigned to accommodate the new RAM. Again given the point-to-point nature, the wiring would be different even if all the connectors were the same (which they aren't).

Then of course those new chips have to be fabbed, tested and made ready for sale, and those boards have to be rolled out. After all that, they still need memory. The memory manufacturers will have to retool their lines and get DDR4 chips and sticks produced in quantity to be sold.

When all that is done, then DDR4 can hit the market and go in your computer (if you purchase a new board, and processor).

So, maybe give it 6-12 months, rather than just bitching at Intel for not "giving a damn"? Just because you don't understand how something works, doesn't mean it is easy to do. Implementing a new RAM spec isn't something you just snap your fingers on, it isn't a tiny patch for software. It is a pretty major thing.

You'll probably see it in systems next year. Intel's roadmap says it will be coming to Haswell-EX server chips first, I haven't seen what AMD's plans are.

Re:Awesome. (1)

jd (1658) | more than 2 years ago | (#40014169)

I would imagine DDR4's higher performance will be important to Intel now that they've designed an even faster Itanium chip (8-core, multithreaded). The power requirement probably wouldn't be much of a factor, though.

1.2V of power? (5, Interesting)

mvdw (613057) | more than 2 years ago | (#40012679)

1.2V of power??!! This is supposed to be news for nerds. Nerds should know the difference between voltage and power.

Re:1.2V of power? (-1)

Charliemopps (1157495) | more than 2 years ago | (#40012765)

Nerds should know Ohms law.
http://en.wikipedia.org/wiki/Ohm%27s_law

and that there is no difference between voltage and power.

Re:1.2V of power? (5, Informative)

AdamHaun (43173) | more than 2 years ago | (#40012859)

Nerds should know Ohms law.
http://en.wikipedia.org/wiki/Ohm's_law [wikipedia.org]

and that there is no difference between voltage and power.

Voltage and power are related, but that doesn't mean they're the same. In fact, Ohm's Law says that they're not -- you still need information about the current (or resistance) to determine power dissipation.

Transistor switching in digital circuits is very different from plain resistance. It's more like charging and discharging capacitors. Energy loss is proportional to voltage squared, at least for dynamic power. That's why lowering the voltage is the most important thing for power consumption.

Re:1.2V of power? (4, Informative)

hawguy (1600213) | more than 2 years ago | (#40012919)

Nerds should know Ohms law.
http://en.wikipedia.org/wiki/Ohm's_law [wikipedia.org]

and that there is no difference between voltage and power.

I don't think you understand the site you linked to. P = I * V -- If power and Voltage are the same, why are they on different sides of the equation?

While it's true that voltage is proportional to power *if* current remains the same, you can't make a blanket statement that a new technology that runs at a lower voltage necessarily uses less power. The old Pentium Pro CPU had a TDP of around 35W with a core voltage of 3.3V, but a new Core i7 can have a TDP of 125W with a core voltage less than 1.5V. Half the voltage, 5 times the power dissipation (and a whole lot more transistors to power)

When dealing with semiconductors, it's likely that lower voltage means less power, but not guaranteed.

Re:1.2V of power? (0)

Anonymous Coward | more than 2 years ago | (#40013421)

I don't think you understand the site you linked to. P = I * V -- If power and Voltage are the same, why are they on different sides of the equation?

I don't think you understand how equations work.

Re:1.2V of power? (0, Troll)

Anonymous Coward | more than 2 years ago | (#40014083)

Everyone knows I is the identity, i.e. one, so P = IV => P = V

Re:1.2V of power? (1)

RandomAdam (1837998) | more than 2 years ago | (#40012939)

No difference between voltage and power.....I would have to say you are wrong!

You can have a potential difference with no circuit, thus no current flow. V=/=P

Re:1.2V of power? (4, Interesting)

mirix (1649853) | more than 2 years ago | (#40012981)

Slashdot needs -1, wrong.

Re:1.2V of power? (1)

Anonymous Coward | more than 2 years ago | (#40013077)

They need negations of all the positive mods. -1 uninformative for things that contain misinformation. -1 unfunny for dumb jokes. etc.

Re:1.2V of power? (3, Insightful)

Anne Thwacks (531696) | more than 2 years ago | (#40013777)

Slashdot needs -1, wrong.

Not nearly as much as it needs -2: Stupid.

Re:1.2V of power? (0)

Anonymous Coward | more than 2 years ago | (#40013157)

Wheres the "flamebait" tag?

Re:1.2V of power? (0)

Anonymous Coward | more than 2 years ago | (#40013391)

Ohm's law just describes the behaviour of resistors. Not everything is a resistor.

Re:1.2V of power? (0)

Anonymous Coward | more than 2 years ago | (#40013525)

Ohm's law just describes the behaviour of resistors. Not everything is a resistor.

Pffft. Quitter.

Re:1.2V of power? (1)

SwedishPenguin (1035756) | more than 2 years ago | (#40013667)

I'm not an electrical engineer, but isn't pretty much everything but superconductors essentially resistors in the sense that they have resistance? For instance wood obviously has a very high resistance, thus why it's not very conductive to carrying electricity.. How would you calculate power where there is zero resistance though? Using Ohm's law, power becomes undefined at that point, and even if resistance in superconductors only approaches zero, would that mean power approaches infinity?

Re:1.2V of power? (1)

Anne Thwacks (531696) | more than 2 years ago | (#40013807)

I'm not an electrical engineer,

That is obvious. Everything may have resistance, but most things have other relevant properties too. Electrical energy can be stores in two ways, capacitatively, and inductively. The determine current every bit as much as resistance in AC circuits. If a significant percentage of the energy is stored momentarily in either of these ways, then Ohm's law no longer describes what happens.

In memory chips, almost none of the power is drawn resistively. Memory chips are an array of capacitors which are switched on and off very fast. The power consumption depends largely on the frequency of switching, and the amount of the memory array that is switched to access one word/byte/why. The power consumption may well depend more on the system supplying the power than the memory array, and most certainly depends on things like caching algorithms more than the detailed chip spec.

what you have here is an argument about the size of the fish they have caught based on the size of the boat they went fishing in. (Car analogy available at extra cost ;-}

Re:1.2V of power? (1)

DeathToBill (601486) | more than 2 years ago | (#40014467)

The complex generalisation of Ohm's law, V=IZ, still describes the behaviour of capacitors and inductors. V, I and Z are assumed in this case to be complex variables of the form e^[j(wt + \phi)], modelling each frequency component independently. w = frequency, \phi = phase offset.

--

Slashdot - news for nerds, stuff that matters, in ISO-8859-1.

Re:1.2V of power? (1)

subreality (157447) | more than 2 years ago | (#40013909)

You have to consider it as a complete circuit. Current (not power) would reach infinity If you had a zero resistance load and an infinite power supply, but those don't happen. Here are some examples to consider:

If you have a 10 volt power supply, 0 resistance superconducting wiring, and a 10 ohm load, you would get 1 amp of current x 10 volts = 10 watts dissipated at the load. Since the wiring has no resistance, its dissipated energy is zero.

If you have a 10 volt power supply, 1-ohm wiring on each side of the load and a 10 ohm load, you would have 12 ohms total which gives you 0.8333 amps x 10 volts = 8.333 watts dissipated total. Each wire will dissipate 0.8333 amps * 0.833 volts (the voltage drop of 0.8333 A through 1 ohm) = 0.694 watts, and the load will dissipate 0.8333 amps * 8.333 volts = 6.944 watts. 6.944 load + 0.694 wire + 0.694 wire = 0.8332 total watts (rounding error from 0.8333), as expected.

Re:1.2V of power? (1)

dbIII (701233) | more than 2 years ago | (#40014035)

even if resistance in superconductors only approaches zero, would that mean power approaches infinity

The superconducting effect breaks down at a fairly low current per area, so it has to be made very thick if you want to have much current. The same applies with electromagnetism since that comes with the current.

Wrong wrong wrong (2)

DeathToBill (601486) | more than 2 years ago | (#40014453)

At least this got modded down, but it's threads like this where you discover how many ignorant 'nerds' there are on /.

Ohm's law does not only describe resistors. While the schoolboy formulation V=IR (also, admittedly, the law Ohm actually published) describes the instantaneous relationship of voltage and current through a resistor, in modern engineering and physics it is generalised in various ways. For circuit analysis, it becomes V=IZ, where Z is the complex impedance, and describes the time-varying relationship of voltage and current in resistors, capacitors, inductors and pretty much anything else you will find in a circuit. For things other than circuits, the generalisation J=E\sigma describes the relationship between electric field intensity, current density and conductivity.

While certain materials are described as 'non-Ohmic', what this really means is that \sigma is not a constant for those materials and depends on something else, usually the value of E.

Re:1.2V of power? (0)

Anonymous Coward | more than 2 years ago | (#40013657)

WTF are you smoking???

Re:1.2V of power? (5, Funny)

tttonyyy (726776) | more than 2 years ago | (#40014017)

there is no difference between voltage and power.

P = V * I

For the purpose of illustration, lets make:

P = pain
V = hardness of slap
I = number of slaps

I'm happy to keep V fixed but increase I until it starts to matter to you too.

Re:1.2V of power? (0)

Anonymous Coward | more than 2 years ago | (#40012767)

Because computer chips use frequency, power consumption scales with the square of the voltage but only linearly with amperage. Voltage is the biggest reason for power consumption for computers.

Re:1.2V of power? (3, Informative)

Bengie (1121981) | more than 2 years ago | (#40013163)

Power consumption for computer chips

C=Capacitance
F=Frequency
V=Voltage
P=Power

P=VC^2F

Capacitance is static, so there are only two variables, F and V. As you can tell, amperage doesn't even play into the equation.

A chip may draw amperage, but that is just a function of C and F.

Re:1.2V of power? (1)

Anonymous Coward | more than 2 years ago | (#40013185)

Plus leakage which is dependent on voltage, temperature and process (fast corner parts have a lot more leakage than slow corner parts).

Re:1.2V of power? (2)

mvdw (613057) | more than 2 years ago | (#40013407)

That is all true, but the units for power are "watts", not "volts". You wouldn't say your car goes 33mpg fast, would you?

It's the way chip power is talked about (1)

Sycraft-fu (314770) | more than 2 years ago | (#40014187)

Again because as the grand parent said, the equation is one of capacitance, frequency, and voltage. So when you produce something of equal frequency, with lower voltage, it'll use lower power. Watts isn't normally specified because that depends on the specific frequency you are using, how many chips, etc. As a designer you can compare the voltage differences to tell you what kind of power savings you can expect. The specifics of that translated to watts is based on your design.

It may not be technically correct, but it is the terminology used and the people who it is relevant to understand it. Also if you think on it a little, it'll make sense.

Re:1.2V of power? (0)

Anonymous Coward | more than 2 years ago | (#40014209)

The P in your equation is expressed in watts which is volts times amps. So amps are right there in the first expression of your equation. Amperage in your equation is a function of C, F, and V. Given the capacity of a typical human I hope you are under 12 years of age.

Re:1.2V of power? (1)

Anonymous Coward | more than 2 years ago | (#40013283)

Also, the voltage was written 1.2v, while the correct format (in the SI system) is 1.2 V, with a space before the unit.

Re:1.2V of power? (0)

Anonymous Coward | more than 2 years ago | (#40014127)

with a space before the unit.

Actually, it's a half space. There is a LaTeX package, siunitx, that does this for you if you're writing a paper.

Re:1.2V of power? (1)

pahles (701275) | more than 2 years ago | (#40014093)

You quoted the post wrong. It said "1.2v of power". Clearly the OP is talking about "the 1.2 version of power". Everybody knows LPDDR uses the 1.2 version of power. Don't you? Please read first and comment later!

Re:1.2V of power? (1)

Neil Boekend (1854906) | more than 2 years ago | (#40014263)

We are still working on version 2. According to my pointy haired boss it will be a synergetic enhanced power package for the most advanced enabeled robust business solutions. :)

Obligatory units complaint (1)

Macman408 (1308925) | more than 2 years ago | (#40012685)

Volts are not a measure of power. Watts are.

More importantly, energy to accomplish a particular task is what really matters. Though usually, we're just given average or typical power numbers. But your mobile device's battery stores energy, not power or potential.

At least the voltage is proportional to power and energy...

Re:Obligatory units complaint (1)

rrohbeck (944847) | more than 2 years ago | (#40013409)

At least the voltage is proportional to power and energy...

Fail.
P=V^2/R.
E=P*T=V^2*T/R.

I'm confused (1)

Muerte2 (121747) | more than 2 years ago | (#40012689)

This may be the most confusing article summary I've ever read. I read it 5 times before I gave up trying to understand it.

Headline: DDR4 May Replace Mobile Memory For Less
Summary: LPDDR3, will further reduce that power consumption (probably by 35% to 40%), it will also likely cost 40% more than DDR4 memory."

Re:I'm confused (1)

Anonymous Coward | more than 2 years ago | (#40012773)

Uh, it makes sense to me.

DDR4 may be used as opposed to LPDDR3 simply because the power savings may not be considered worthwhile when the RAM is 40% more expensive. What the summary fails to explicitly point out is that DDR4s power envelope roughly matches LPDDR, which I guess is why it's considered "good enough" all of a sudden. Presumably this means cheaper devices may go DDR4 to save a bit of cash, whilst premium devices may opt for the more expensive solution to squeeze a bit of battery life out.

Either way you look at it, we're getting newer better stuff. Tis a good thing. :)

Re:I'm confused (0)

Anonymous Coward | more than 2 years ago | (#40012789)

DDR4 uses about as much power as current LPDDR. The next iteration of LPDDR will use less power than DDR4, but because it will be more expensive, DDR4 will gain market share in the mobile space.

Re:I'm confused (2)

ChunderDownunder (709234) | more than 2 years ago | (#40013333)

If I understand correctly, LPDDR2 draws significantly less power than DDR3.

DDR4 will be competitive with LPDDR2.

But in turn, LPDDR3 will draw significantly less power than DDR4.

So manufacturers will have the choice of preserving today's mobile power levels by going with DDR4. Or they can use a more expensive LPDDR3 with lower power but, presumably, lower performance.

One picosecond later... (1)

Anonymous Coward | more than 2 years ago | (#40012751)

...a significant boost in software bloat to nullify all that great hardware progress. I'm still stunned as to why anything takes perceptible time on a modern computer. Things should just pop and wink into existence at the merest click.

Re:One picosecond later... (0)

Anonymous Coward | more than 2 years ago | (#40013091)

Most of the issue of slow responses is poor user app programming and design. If people used proper async and threading, all would be well... other than waiting on IO.

Re:One picosecond later... (1)

Kergan (780543) | more than 2 years ago | (#40014273)

If people used proper async and threading, not many programs would work. I'm not sure I know 10 coders who reliably deliver thread-safe code.

Spec water-torture (0)

Compaqt (1758360) | more than 2 years ago | (#40012783)

What I hate about "New tech XYZ increases throughput by 2x!" is:

Why didn't they simply specify the high transfer rate in the original spec (as in USB)?

Why didn't they simply specify a lower voltage in the first place (for memory)?

Re:Spec water-torture (5, Funny)

pushing-robot (1037830) | more than 2 years ago | (#40012821)

Yep, it makes you wonder why we bothered with old technology at all. Why didn't we start using today's computers fifty years ago? Think of all the time and effort it would have saved!

Re:Spec water-torture (3, Informative)

blueg3 (192743) | more than 2 years ago | (#40012849)

In order for a spec to be useful, you need to be able to actually build the specified system. The reason they don't encompass things that they can't currently build in the specs is that they want the specs to be useful.

Re:Spec water-torture (0)

Anonymous Coward | more than 2 years ago | (#40013385)

In order to NEED/use lower voltages, you would need smaller transistors first. Why not go to single atom transistors now instead of 20-ish nm?

Can't do much when you don't have the fabs nor geometry back in the DDR1 days. All they had was 2.5V node.

Remember this is a practical trade engineering specs that can be used to build actual products not a white board wish list.

Re:Spec water-torture (1)

batkiwi (137781) | more than 2 years ago | (#40013441)

Technology to make it work at X speed and Y voltage didn't exist at the time, and for something like a memory module you don't design it to take a range of voltages or speeds.

Re:Spec water-torture (2)

jd (1658) | more than 2 years ago | (#40014217)

As others have noted, the tech wasn't there.

However, in the more abstract sense, you can only extrapolate models so far beyond the furthest point for which you have data before the models break down. But you don't know when that will happen, it depends on how good the model is and you can't know that in advance.

Specs are therefore reasonably conservative. They'll go a little bit beyond what's feasible right now, but only a little. Just enough to give wiggle-room and space for progress, but not to the point where there's a serious risk of problems developing.

Examples of reasons why they need to be careful: both electron tunneling and thermal noise will generating errors, yields at lower scales aren't always predictable, alternative techniques for performing the same function at the higher speed can be incompatible with accelerating the original technique, etc.

A spec is supposed to work for anything it is a spec for - manufacturers do revise/debug specs but they vastly prefer to release upgraded versions as compatibility issues and implementation details can all be carefully documented and properly presented.

Increment numbers (2)

magarity (164372) | more than 2 years ago | (#40012879)

I'm glad they keep it reasonably simple with DDR(1), 2, 3, and now 4. I dread the arrival of RAM2015 or somesuch nonsense one day.

Re:Increment numbers (0)

Anonymous Coward | more than 2 years ago | (#40013047)

You mean like:

Low Speed
Full Speed
High Speed
Super Speed
Light Speed
Ludicrous Speed!!!

from the not-dance-dance-revolution dept. (5, Funny)

tepples (727027) | more than 2 years ago | (#40013141)

After DDR5, there'll probably be DDRMAX, DDRMAX2, and DDR Extreme, if history is any indication.

Re:from the not-dance-dance-revolution dept. (0)

Anonymous Coward | more than 2 years ago | (#40013361)

That'd be pleasantly amusing if they do name them that. Not holding my breath though.

Re:from the not-dance-dance-revolution dept. (1)

rrohbeck (944847) | more than 2 years ago | (#40013419)

Too bad Hyper was already taken.

Re:from the not-dance-dance-revolution dept. (1)

Kergan (780543) | more than 2 years ago | (#40014255)

Or they could borrow a page from phone manufacturers: DDR Desire, DDR Sensation, DDR Cruise, DDR Intensity, DDR Vitality, etc.

Re:Increment numbers (0)

Anonymous Coward | more than 2 years ago | (#40013811)

somewhat. GDDR could cause a bit of confusion.

Costs less? (1)

Anonymous Coward | more than 2 years ago | (#40013125)

I don't care if it costs less. What are they selling it for?

Meh (1)

supersloshy (1273442) | more than 2 years ago | (#40013439)

I'm waiting for DDR MAX 2 and DDR Extreme. The difficulty level in the early ones is just- ... Ohhh we're talking about memory here. Carry on, folks. Ignore me.

DDR4 won't replace LPDDR3 (0)

Anonymous Coward | more than 2 years ago | (#40013563)

I'm not convinced.

Mike Howard claims DDR4 will be 40% cheaper than LPDDR3, but this claim is unsubstantiated in the article. Volume for LPDDR3 will be high, and it's not like there's anything EXTRA on LPDDR3 chips; quite the opposite!

In fact, LPDDR3 has no I/O termination, no local clock regeneration, and will ship mostly x16 and x32 parts. This all translates to significant energy-efficiency advantages. It also means that it's a bitch to deploy more than a GB or two of LPDDR3, which is why you don't see LPDDRx in servers or desktops.

I don't doubt that DDR4 will find its way into some low-end tablets, but they'll probably suck. If they compromise on memory, what else did they compromise on? I will be pretty surprised if you see it much in cell phones.

Re:DDR4 won't replace LPDDR3 (1)

kyrio (1091003) | more than 2 years ago | (#40013779)

You aren't too current on the last 20 years of RAM prices, are you? LPDDR costs a lot of money compared to DDR.

Why not go to DDR5? (1)

Anonymous Coward | more than 2 years ago | (#40013987)

Some graphics cards have GDDR5 in it, why not use that?

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