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Is Your P4 Working At Half Speed?

timothy posted more than 13 years ago | from the boy-it's-hot-in-here dept.

Intel 217

ArneD writes: "While browsing xbitlabs.com discussion-board I found this message about the P4. The message suggests that the P4, when stressed and getting hot, starts to halt 50% of the time. When checking mail your precious P4 works at 1.5Ghz but when used for something meaningful (recompiling your kernel?!? ;-) the processor may in fact be a mere 750Mhz since it starts to issue PROCHOT signals that tells the processor to switch itself on/off 50% of the time until it's temperature is within Intels spec-range again." (Read more.)

"More information can be found in Intels Pentium 4 Thermal Design Guidelines (check out page 23)."

Several readers have submitted news of this clock-throttling, one aspect of the P4's built-in temperature sensor system Intel calls "Thermal Monitor." One thing to point out is that the same design guidelines document goes on to say that "the clock modulation feature of Thermal Monitor is disabled by default ... OEMs are expected to enable the thermal control circuit while using various controls and outputs to monitor the processor thermal status." Other things being equal (even if they never are) is there some reason to prefer a chip for not having this capability? If someone forced me to accept a free and loaded P4 system, I'd rather it be cool down at 750MHz temporarily than toast at 1.5GHz.

cancel ×

217 comments

1.5GHz is fraud. Should be labeled like CDROMs. (1)

Anonymous Coward | more than 13 years ago | (#288480)

Those CPUs should say 1.5GHz MAX like CDROMs are labeled 48x MAX and such. Time for the FTC to smack Intel around. Hell, I'm surprised Intel isn't quoting their MHz in octal. The 2.73GHz P4! Oh wait, that's base 8.

Pentium 4 (1)

Anonymous Coward | more than 13 years ago | (#288481)

...proudly designed for the 100-meter dash. If your task is the biathlon, then we suggest buying a dual-athlon.

Unpossible!! (2)

Anonymous Coward | more than 13 years ago | (#288485)

pentium4 comes directly from God, and questioning God's precision is blasphemous

Re:is there some reason? (2)

Anonymous Coward | more than 13 years ago | (#288486)

Yup, linuxppc [linuxppc.com] is pretty cool.

Picking a nit (1)

phil reed (626) | more than 13 years ago | (#288487)

I can feel warm air coming off the base, but most of the heatsink is below room temperature.

The only way the heatsink can be below room temperature is if there is active cooling involved. (There might well be, but I've not seen it on Orb-type heatsinks.) The reason metal feels cold is that it conducts the heat away from your skin faster than air does. Your nerves mis-read this as "cooler".


...phil

Morons.. (1)

Edge (640) | more than 13 years ago | (#288488)

Some people seem to think this is some huge conspiracy by Intel against the consumer. Far from it. All of you overclockers should be well versed in the need for adequate cooling for your CPUs. Apply the same cooling procedures to your P4 and it'll run at full speed. Put some old brushless 1500 rpm fan and a crappy heat sink with no thermal compound under it on your chip and it's going to overheat.

Why is it a problem that a chip has a feature built in that slows down the clock speed when it begins to overheat?

Am I missing something here?

Would you rather your poorly cooled, poorly ventalated system go into thermal meltdown?

well... (2)

pb (1020) | more than 13 years ago | (#288491)

Although that's not really acceptable for a released, commercial processor, I must say that it sure beats overheating!

Why can't processors dynamically adjust their clock speed based on temperature in the first place? Transmeta does this somewhat, but it'd be nice if my chip could overclock itself, insofar as that is safe. :)
---
pb Reply or e-mail; don't vaguely moderate [ncsu.edu] .

Re:well... (1)

shrike (1090) | more than 13 years ago | (#288493)

I sincerely doubt you'd want that. If your CPU was able to achieve 2000 MHz, when not under load and 600 MHz when under load (hot), I'm pretty sure they'd sell it as a 2 GHz and not a 600 MHz processor (like with the P4). Apart from this, the idea is interesting.

Re:A reply from Intel at [H]ardOCP (2)

Ex-NT-User (1951) | more than 13 years ago | (#288495)

Notice however that his statement of 100% utilization was accompanied by "I track its performance and I can assure you that it has not ever slipped into the throttling"

He is not saing that he expected the cpu utilization to drop top 50%, He is saing that he is running his apps at 100% cpu utilization and didn't notice any performance drop.. meaning that his cpu never kicked into the throttle mode. This 100% is meant to say that he is STRESSING his cpu.

Re:Whoops! (dual p4) (2)

iabervon (1971) | more than 13 years ago | (#288496)

You can have a dual p4; you just have to have one of them disabled at any given time...

Actually, I wonder if they could build a motherboard where, if one CPU got too hot, it would switch over to the other one.

Re:Good heatsink (1)

cdipierr (4045) | more than 13 years ago | (#288498)

I think you should ammend your "many people have burnt or cracked their chips" with "people who do not follow AMD's cooling recommendations or improperly try to force a non-socket A cooler on to their chips".

Re:my god! (4)

otis wildflower (4889) | more than 13 years ago | (#288499)

Well lets just strap a box-fan on the side of the thing!!

Hehehe looks like someone did [envador.com] ..

Your Working Boy,
- Otis (GAIM: OtisWild)

Alrighty then. (2)

Chris Burke (6130) | more than 13 years ago | (#288501)

Okay, so this clears things up a little.

So, basically,

1) if you have proper cooling, it won't ever come into play (which sounded like it was the case anyway, since none of the benchmarks seemed to show this behavior)

2) it is still somewhat underhanded to advertise the part as having a power consumption of 54W, making the P4 seem as though it consumes less power than the K7.

3) it is still pretty silly for AMD _not_ to have some kind of thermal protection (though again, if you have proper cooling, it shouldn't be a problem).

Now that we've got that cleared up...

No rumor. (2)

Chris Burke (6130) | more than 13 years ago | (#288502)

It's not a rumor, the thing exists! A 4-way Foster (codename for the Xeon part) system called P-Shasta (which I got to work on! =D) was demoed last year.

As to why it ain't out yet, I can't tell you. Sorry.

Re:hype. (2)

Luke (7869) | more than 13 years ago | (#288504)

....Stanford University now for a solid month and has stayed at 100% CPU utilization.

Remember, 100% utilization at 1.5Ghz is going to look the same as 100% at 750MHz. The useful info would be to run a program alongside that could monitor the current clock of the CPU. Either that or keep track of your work submissions to make sure they don't drop off.

Intel to Slash P4 Prices by 50% (2)

mathboy (10519) | more than 13 years ago | (#288508)

I think intel made the announcement to drop prices to cover for this embarassing admission - so you still loosely 'get what you paid for'.

Sounds fair to me.

It's not a big change... (2)

Faldgan (13738) | more than 13 years ago | (#288513)

Some people (usually overclockers) have been doing something similar to this for quite a while. The way it's worked until now is that they run a program (waterfall for windows, or automatic under Win2k and {of course} Linux) that issues the idle command if the processor is otherwise idle. This saves energy, reduces heat, blah, blah, blah.
The problem is then exactly the same as here:
You've got a super-fast CPU, but you can't actually use it for long, intensive tasks.
(i.e. 5 minutes into a game of Quake, the system will become unstable)
The solution? *shrugs* Hard to tell. Wait for a CPU that won't do this. (AMD!) and don't overclock so much.
Note: I love overclocking. I've overclocked every system I've had since my 483/33 My current main system won't overclock more than 5MHz. Life sucks for me. But I'll overclock my next system.

Wombats: The Bulldozers of the Bush.

Re:Is Your P4 Working At Half Speed? (5)

Silver A (13776) | more than 13 years ago | (#288514)

Is Your P4 Working At Half Speed?

No, reading Slashdot isn't THAT taxing on my cpu.

Unless you're using Mozilla.

Geez, and to think all this time... (1)

alienmole (15522) | more than 13 years ago | (#288515)

...I've been feeling guilty about reading /. and surfing when I'm supposed to be working.

Thanks for explaining this!

I smell FUD!! (1)

hari (15720) | more than 13 years ago | (#288516)

Is any on this true ? Anyone found any links which can warrant this story ? Seems like slashdot is upto it's bang up job of screening !

Grok the Demon !

Re:Effecient engineering (1)

Neon Spiral Injector (21234) | more than 13 years ago | (#288523)

Intel is rumored to be making a Xeon P4 that will have SMP capabilities.

I'm waiting for an SMP motherboard for the Athlons.

Who knew (1)

Ledge (24267) | more than 13 years ago | (#288526)

Wasn't this previously a feature in the mobile line? Or did the mobiles throttle merely for battery life? I fail to see a problem with the feature as long as adequate cooling can be achieved that will allow you to run intensive apps without throttling coming in to play 95% of the time. Better this I suppose than the ease of frying Thunderbirds that I have heard about. Don't get me wrong, I'd rather have an Athlon than a P4 myself, but I about crapped when I saw Patrick Norton on The Screen Savers on TechTV frying Athlons merely by booting for a couple of seconds without a heat sink installed.

Re:well... (3)

bogado (25959) | more than 13 years ago | (#288528)

The only problem with this is the custumer that payed more money to have a fast machine and when he need the speed the processor get's 50% slower. I think this is a great feature, but something like this should be known to all, not hidden in some obscure tech documentation.
--
"take the red pill and you stay in wonderland and I'll show you how deep the rabbit hole goes"

A reply from Intel at [H]ardOCP (4)

OtakuMan (27083) | more than 13 years ago | (#288529)

Copied Verbatim from www.hardocp.com

Now that you guys have had a couple days to get excited about what Bert McComas had to say about the P4 clock throttling itself, I thought I would throw in my two cents. First off, here is the statement that is stirring the pot so well.

Intel's Thermal Design Guide has revealed that the absolute maximum power dissipation of the 1.5GHz P4 is actually 72.9 watts. This is 33% higher than the published system design specification, and essentially identical to the 1.33 GHz Athlon. In order to prevent the CPU from exceeding 54.7 watt, thermal throttling is used. If performance critical applications drive CPU power above its artificially low 54.7 watt limit, the CPU is halted with a 50% duty cycle (alternating 2 microseconds on; 2 microseconds off) until it cools down. This effectively turns your 1.5GHz processor into a 750MHz processor - just at the moment you demand peak performance. On the other hand, you will probably still be able to check your email at 1.5GHz.

While I don't know Bert, I have had the pleasure of meeting him and you have seen his links here on the [H] many times. On this occasion I think Bert has been sucking the crack pipe a bit too hard or either must have been in a terrible auto accident and had his cranium lodged in his rectal cavity and did not notice before he wrote the above statement.

We have been running an over-volted overclocked Pentium4 with the factory heatsink installed now for some time. It has been running here beside my desk folding proteins for Stanford University now for a solid month and has stayed at 100% CPU utilization. I track its performance and I can assure you that it has not ever slipped into the throttling that Bert speaks about above. If Bert's apps are running at 50%, it is because he does not have the sense to put a heatsink on the CPU or either he is operating his P4 system in Hell. Bert is taking an Intel safety device and demonizing the P4 with it. Here is what Intel PR George Alfs had to say about Bert's statements.

Hi Kyle,
You can run benchmarks all day on a Pentium(R) 4 processor with the benchmarks unaffected by the thermal protection circuitry. The key is to have a robust heat sink and thermal solution. With the heat sink setup we designed for Pentium 4 processor systems, I have yet to see thermal protection kick in.
George.

I have to fully agree with George's statements and have a few things to add. Also, I think that "robust" need not be in his statement.

What Bert may not know is that some mainboards have an adjustment in the BIOS that you can set yourself with the temperature that you want throttle to. (On our systems we have left it at default and never messed with the settings on the particular board that is Folding.) Yes, YOU can turn this on and off and fully control it on some mainboards. If you want a shield in between you and a burned up processor, set it low; if you want to forego the safety feature, set the temp high. I know that MANY of you wished that AMD had the courtesy to include a feature such as this instead of leaving their Athlon and Duron CPUs totally unprotected.

We have never seen nor heard of the CPU throttling being active on any person's CPU and certainly have not experienced it ourselves (unless we FORCED it to happen) under conditions more strenuous than 99.9% of the P4s in the field will ever encounter. I do not suggest that DIYers or hobbyist go the P4 route if they want to buy a system for themselves, but bashing it on this front is simply bad journalism and transparent to many people.

We here at the [H] have a lot of respect for Bert McComas' work and think he should step back up to the plate and possibly rephrase the statements in regards to this issue. Bert, we love you man, but you were just totally out to show Intel in a bad light this time, or were simply not thinking through the issue properly because you are being misleading and it looks to us as if you were trying to do it purposefully.

Motherboard Shutdown Feature (2)

Izaak (31329) | more than 13 years ago | (#288534)

I recently bought a cheap-o locally built 700Mhz Celeron system to turn into a Linux server. It would run for several days and then shut itself off. After a bit of digging, I learned that the motherboard had a feature to actually shut down the entire system if it became too hot. I moved the box to a better ventilated area and it has been rock solid since. Really had me scratching my head for a while though. :)

Later,

Thad

Abuse (1)

Spyffe (32976) | more than 13 years ago | (#288535)

Although this may not be strictly speaking illegal, it is stupid to reward this kind of wholesale copying from another site with a +3 moderation.

Slashdot would not be happy, for example, if someone began collecting their more interesting articles and reproducing them elsewhere. Hyperlinks were intended for a purpose! HardOCP deserves to have its content seen on its site, IMO.

Although this instance of a post copying from another site (in this case HardOCP) may have been purely informational, the concept that messages with no original content can get modded up may become an encouragement for ACs, and eventually force less genial folks than Kyle to step up their actions, a la Church of Scientology.

Posts exist to publicize original content. What has been done here is not that.

this is a bad thing? (1)

Spiral Man (33998) | more than 13 years ago | (#288536)

my asus a7v has software that monitors the cpu temp, and then clocks down if it goes above a certain level, of course, in this case, you can set the level, and i dont think it works the same way...

i believe it actually lowers the clock speed, but im not sure how much...

if there was more controll, this would be a good feature for overclockers, or people who have to operate their computers in a hot environment. i would rather have my computer run slower, than have to buy a new one because i burnt it out

Re:A reply from Intel at [H]ardOCP (2)

atlep (36041) | more than 13 years ago | (#288538)

We have been running an over-volted overclocked Pentium4 with the factory heatsink installed now for some time. It has been running here beside my desk folding proteins for Stanford University now for a solid month and has stayed at 100% CPU utilization. I track its performance and I can assure you that it has not ever slipped into the throttling that Bert speaks about above.
Of course it will be 100% CPU utilization. No matter what MHz it is running on, as long as there is work for the CPU, it will run at 100% utilization. It's not like when the clock speed drops, suddenly the work load will drop too.

setiathome (1)

csbruce (39509) | more than 13 years ago | (#288539)

So what happens if I run SETI@home? My current CPU is going 100% all of the time. (Or, at least the FPU is.) If (heaven forbid) I were to get a P4, would I be getting 50% performance all of the time? Why not just buy a 750-MHz CPU!

Big deal the PIII does it too... (2)

bored (40072) | more than 13 years ago | (#288541)

The PIII Systems Programming guide [intel.com] has a section on thermal control for the P6 core as well. Read chapter 12: System Management 12.14 Thermal Monitoring. On the P6, software can directly control the duty cycle or a default behavior can be programmed in to take affect when the system goes over a certain temperature. The on demand clock modulation can be a lot worse than 50%, the values range from 12.5% to 87.5%... Oh, BTW this stuff is almost always controlled by the BIOS so running linux won't change its behavior.

Re:Moderators, this is REDUNDANT (1)

GoofyBoy (44399) | more than 13 years ago | (#288542)


I always thought that Redundant applies to when it is a duplicate of another slashdot comment. Calling it Redundent makes it sound like it contains no new information.

How about Overrated?

Wait a second... (2)

DanThe1Man (46872) | more than 13 years ago | (#288545)

Does this mean that people who over-clock thier P4 systems are auctually likely to SLOW their cpu down?

Is Your P4 Working At Half Speed? (2)

DanThe1Man (46872) | more than 13 years ago | (#288546)

Is Your P4 Working At Half Speed?

No, reading Slashdot isn't THAT taxing on my cpu.

I work at half speed... (5)

MustardMan (52102) | more than 13 years ago | (#288548)

When things get too hot at work I switch into my brain-cooling mode. I spend 0.2 microseconds working then switch off to slashdot reading mode for 2 seconds. This modified duty cycle allows time for my brain to cool down. Once frustration levels are within acceptable tolerances, I switch back into 100% work mode.

Re:Good heatsink (1)

Weezul (52464) | more than 13 years ago | (#288549)

Actually, my 1GHz Athlon frequently slows to a crawl when I'm doing disk access. I assumed is was something brain dead about the VIA chipset which would be fixed in the next kernel, but I suppose it could be related to the CPU. Any ideas?

Jeff

Moderators... this post is sarcastic (2)

Illserve (56215) | more than 13 years ago | (#288550)

Read the end, he isn't serious. Give him a Funny or 3.

Re:Effecient engineering (1)

Kalper (57281) | more than 13 years ago | (#288551)

You will be waiting forever as the chip was designed with no SMP capability == multi-processor P4 is not possible.

Cookers (1)

IAmATuringMachine! (62994) | more than 13 years ago | (#288555)

What good is a supafast processor if it drops to half speed when doing anything useful? Is this how Intel is getting the faster pentiums out the door? I'm quite happy with my G4, thank you very much...

--
"Computer Science is no more about computers than astronomy is about telescopes."

Re:Cookers (1)

IAmATuringMachine! (62994) | more than 13 years ago | (#288556)

forgot to mention... no fan :)

If Nixon were on /., he would say
"I am not a troll."

--
"Computer Science is no more about computers than astronomy is about telescopes."

Re:Cookers (1)

IAmATuringMachine! (62994) | more than 13 years ago | (#288557)

You know, I hadn't considered that option. Now I need a new sig...

--
"Computer Science is no more about computers than astronomy is about telescopes."

Re:Good heatsink (1)

norton_I (64015) | more than 13 years ago | (#288560)

Whether the throttling is a good thing is up to debate (and I say it is good: If you don't properly cool your CPU it won't melt down!). However, it appears that Intel *still* mis-represented the power consumption, which is something Intel advocates have been bashing AMD over. In particular, people have claimed that the Athalon will have problems scaling because of its high power consumption. It looks to me like the P4 will face the same problem.

Re:Effecient engineering (1)

Rares Marian (83629) | more than 13 years ago | (#288568)

Sure, you might only get half the clock cycles, but the ones you do get, are two times faster, so you are getting even more performance than a regular chip!

? What ? the ? hell ? are ? you ? talking ? about ?

Re:hm (1)

colnago (91472) | more than 13 years ago | (#288570)

or here:

slashdot [slashdot.org]

is there some reason? (5)

Paradise_Pete (95412) | more than 13 years ago | (#288575)

s there some reason to prefer a chip for not having this capability?

Perhaps there's a reason to prefer a chip that doesn't get so hot in the first place. I heard Motorolla and IBM make one, and that some company has released a Unix variant that runs pretty well on it.

Hey timothy.. I can cut and paste too! (2)

vultureman (98555) | more than 13 years ago | (#288577)

The article says that a thermal diode is responsible for triggering the throttled-down performance. But then it also says that the throttling happens due to the power consumption. These are different things: power consumption only causes the temperature to rise if the cooling is not slurping off excess heat fast enough.
Anyone care to comment on this seeming discrepancy?

Assuming that it really is thermal throttling, I would love to see what a good tech site like Tom's might be able to determine about the throttled down CPU when using various heatsinks. If that feature is really there then you should expect more powerful heatsinks give the same temperature as lesser heatsinks, but higher performance.

In other words, it is possible to see this as a feature, not a bug. You get 1.5G when the processor is capable of it. You get half that when you are running hot; but with good enough cooling you should always get the highest performance possible.

"Overclocking" may go away, replaced by "overcooling".

-- props to Wreck (leonard@dc.spam.net) --

Re:well... (1)

The_Messenger (110966) | more than 13 years ago | (#288580)

Why can't processors dynamically adjust their clock speed based on temperature in the first place?
My Athlon Thunderbird does this. Around 90C, it dynamically adjusts its clock-speed to 0MHz.

--

Re:is there some reason? (1)

The_Messenger (110966) | more than 13 years ago | (#288581)

Not to mention Sun. My 500MHz UltraSPARC III kicks x86 ass and doesn't even require a fan.

--

Re:well... (5)

The_Messenger (110966) | more than 13 years ago | (#288582)

Why can't processors dynamically adjust their clock speed based on temperature in the first place?
My Athlon Thunderbird does this. Around 90C, it dynamically adjusts its clock-speed to 0MHz.

--

Re:And what will the wider consequences of this be (1)

welthqa (111199) | more than 13 years ago | (#288583)

...computers do all we need them too.

no way. until my pentium 9 is running around in a black teddy fixing me martinis and giving me blowjobs, there is a lot more we from them. ;)

This was discussed a few days ago (1)

moogla (118134) | more than 13 years ago | (#288587)

In this slashdot article [slashdot.org] about a Pentium IV study [inqst.com]

Read those before you reply about the PIV power situation (hint: if you cool it, it won't cut itself down to half speed). But it wasn't nice that Intel forget to mention the thermal diode is what allows that theoretical lower-than-Athalon power consumption; you won't see that benefit if you massively cool it.

Whoops! (dual p4) (1)

moogla (118134) | more than 13 years ago | (#288588)

> I can't wait to get myself a dual proc p4! Intel's P4 architecture does not support SMP. Anything to get that clockspeed in the microwave range! That's Intel innovation for you.

Thats why you need a real case (1)

QuantumRiff (120817) | more than 13 years ago | (#288590)

I use the Supermicro 750-A, here [supermicro.com] Mine has 11 fans in it. It sounds like a wind tunnel in my bedroom, but you practically have to chip the ice of the system!!!

------------------------------------------
If God Dropped Acid, Would he see People???

Re:Good heatsink (1)

donglekey (124433) | more than 13 years ago | (#288592)

I will use this oportunity to plug the Super Orb. I got one and used it on a Thunderbird Athalon 950 Mhz, and I could easily overclock it more, it works that well. I can feel warm air coming off the base, but most of the heatsink is below room temperature. It rocks. I think it costs maybe $15 if that, there is no excuse not to get one, unless you are getting a golden orb or one of the huge copper/aluminum heatsinks.

Re:And what will the wider consequences of this be (1)

Hellburner (127182) | more than 13 years ago | (#288593)

"Better to stand still in a meadow of sweet flowers than run forward across the bombpitted, mined and chlorine gassed no man's land of technological advance" is 'informative'?

Hello? What the fuck, folks. Funny, maybe, if a bit ham-fisted. Flamebait, certainly. Troll, assuredly. Look, I like to curl up with a good Philip K. Dick novel and 70 ccs of misery as much as the next guy but my GOD, people.

So...the tribulations of the P4 are going to lead to the stable Chung Kuo heavenly realm of techno-stasis. This is as fucking stupid as the gobot writing how open-source was communism the other day. Shouldn't Katz be writing this bullshit? Or at least interviewing someone about it?

Looks like I'm going to have to re-animate Heinlein's corpse with a team of crack commandos and surprise the fuck out of a lot of people. No stupider idea than this pile of mental dung.

Last weeks news (1)

El Prebso (135671) | more than 13 years ago | (#288597)

This not really news, other sites had this story a week ago. I actually think i saw it on Slashdot last week, well proberly not

AMD T-bird = Better cpu! (1)

Sonicboom (141577) | more than 13 years ago | (#288599)

I've got a 1Ghz PIII at work and an AMD 1ghz athlon at home - both running Slackware on them and HANDS DOWN the Athlon kicks the PIII's ass!

It's better for GiMP, and it even runs the DISTRIBUTED.NET RC5-64 keycracking client faster!

(I'm getting 3.5 million keys/sec on the Athlon!)

Oh - and I forgot to mention the price difference between the 2 chips - go to Pricewatch.com to see the difference!

AMD - more bang for your buck!

This has always been a problem (1)

HerrGlock (141750) | more than 13 years ago | (#288600)

Heat causes weird things to happen with computers. Radio shack and just about every computer store on Earth sell 3" fans that plug into drive power supplies that you can put anywhere in your case. Whenever I get a new computer that is the first thing I get to put in, blowing directly onto wherever the CPU is. If the case supports it, I get two or three of them for the front of the case to blow in and the rear of the case to blow out. Yes, CPUs get HOT and the more air you can move around/over them the better off you are.

DanH
Cav Pilot's Reference Page [cavalrypilot.com]

I couldn't imagine a P4 at half speed... (1)

piku (161975) | more than 13 years ago | (#288606)

Lets see, if a 1.2ghz Thunderbird kills a P4 at 1.5ghz, so then what... I guess my P60 would kill at Pentium 4 750mhz.

Re:I couldn't imagine a P4 at half speed... (1)

piku (161975) | more than 13 years ago | (#288607)

I suppose I should have added a smiley or 4 in my original post.

:)

Re:AMD T-bird = Better cpu! (2)

OhPlz (168413) | more than 13 years ago | (#288610)

And that has what to do with the article? You're comparing a PIII vs an Athlon, neither of which is a P4. Besides that, there's a great number of things that can affect performance. The processor is but one of them.

Re:Moderators... this post is sarcastic (1)

John Jorsett (171560) | more than 13 years ago | (#288611)

Read the end, he isn't serious. Give him a Funny or 3.

I was about to moderate him up +1: Funny, but someone beat me to it with a +1: Insightful, and it's at +5 now. Ah well.

But in the document... (3)

taliver (174409) | more than 13 years ago | (#288613)

Page 26, they have a neat little graph that says that if the chassis has 70% of some optimal cooling capacity, the throttling won't happen. So since this is will keep an overheated processor from being cooked, I can only see this as a positive.

Re:Mac tests? (1)

CottonEyedJoe (177704) | more than 13 years ago | (#288615)

I run mostly on Apple hardware (I have SGI, sparc and IBM RS6k too) but I SERIOUSLY doubt that a 733 MHz G4 Mac is as fast as a 1.5 GHz PIV, though I would easily believe its faster at the same clock rate. From all the "properly cool your chips" posts I'd say any professional benchmarking was conducted with a setup with adequate cooling. For Folks looking to really cool down their intel chips, try and find a used SGI indigo2 case and rip the fan out of it. Talk about a HYOOGE fan. When will we see intel and AMD pushing refrigeration units for their systems? Better be fast...multicore G5's are on the way.

Mac tests? (1)

Teflon Coating (177969) | more than 13 years ago | (#288616)

You know how they always compare the Macs to the PCs and show how the mac is faster? I wonder if those benchmarks reflect the processor at 1.5ghz or 750mhz. Is the pentium IV @ 750mhz when most benchmarks are done? If this is so then why is it still faster than a 750mhz machine(except for a mac :-) )?

[H]ardOCP response... (3)

FooManChuYouMoo (183196) | more than 13 years ago | (#288618)

The guys at [H]ardOCP [hardocp.com] addressed this issue. Look under Sunday, April 15, 2001 - Ed 2. "We have never seen nor heard of the CPU throttling being active on any person's CPU and certainly have not experienced it ourselves (unless we FORCED it to happen) under conditions more strenuous than 99.9% of the P4s in the field will ever encounter. I do not suggest that DIYers or hobbyist go the P4 route if they want to buy a system for themselves, but bashing it on this front is simply bad journalism and transparent to many people." Sorry, I don't know of a way to direct link to an article on their site...

Re:Effecient engineering (1)

mbourgon (186257) | more than 13 years ago | (#288619)

I figured that the original post was 5:Humor, not 5:Insightful. I think it's supposed to be funny, but a little too serious for its own good.

Re:Mac tests? (1)

Jaysyn (203771) | more than 13 years ago | (#288627)

because....and I don't know how many times it's going to take for people to realize this...Mhz don't mean shit....especially with a Mac...two completely different processors....like apples & oranges, get it?

Jaysyn

Wonderous technology! (1)

QwkHyenA (207573) | more than 13 years ago | (#288629)

How wonderous that Intel would develop and release a chip that is self throttling in its favor. Why don't they release the chips as P7's and tell us "while not being used it's the fastest CPU on the planet!, but under strain, it throttles down to a 486 speed to avoid heat stress..."

I'll take two please!

I'm surprised they haven't used buzz words like 'Smart chip' or 'Evolution Technology!'

Crap, if they do...I want royalties!!

Cheap argument tricks [OT] (1)

LuckyLuke58 (207964) | more than 13 years ago | (#288630)

It is well known that the development ..

I'm wary of anyone who puts forth an argument using these words. They are most commonly just a cheap way of trying to give one's statement(s) extra "weight" in an argument, without having to worry about the hassles of actually backing up your arguments with references. It also has the additional benefit of discouraging people from disagreeing, since the fact is obviously so "well known", then if you don't happen to agree with it, you must be in a small minority and are probably wrong, so you keep quiet so as not to sound stupid.

I can't say I've ever read a scientific research paper that began with "it's a well known fact".

Related variations of this are "it's a little known fact ..", "experts say ..", and of course the real marketing derivative, "scientists tell us ..".

The sad thing is that these things work on most people. I wish they'd teach all these cheap tricks in school. Perhaps the public would spot these things then, and be harder to fool. Then again, most sheeple probably prefer having their opinions handed to them on a platter, rather than having to form opinions themselves.

Sorry .. this isn't a response to your post at all, just a general OT rambling ..

Overclock Defense??? (1)

kstumpf (218897) | more than 13 years ago | (#288643)

Most overclockers know Intel frowns upon overclocking. What implications does this throttling have on overclocking the P4?

When overclocking, your biggest obstacle is typically heat. If I increase the voltage to my chip, and this temperature protection kicks in, I could be running alot slower than if I were underclocked!!

Personally, I don't know of anyone who's been able to overheat a CPU. I've always heard overheating shortens its lifespan, but I don't use a CPU more than a couple of years anyway and don't really care. I'm actually still running on an overclocked Celeron 300A at 450Mhz.

Re:Deja Vu... (1)

Microsift (223381) | more than 13 years ago | (#288645)

Well d'uhhh, if the computer is half as fast, it makes sense the story would be posted twice! 1/2*2=1!

Thermal throttling, not power throttling (1)

esses (223521) | more than 13 years ago | (#288646)

If you know _anything_ about a silicon....you know that it's conductive properties are extremely coupled with temperature. I'm going to be deliberately dumbed down for the masses... The thermal diode is nothing more than an extra P-N junction on the actual processor core. As the temperature of the actual silicon die changes, the effective resistance of the diode will change and allow a current to flow through it. The amount of current that flows through the diode is somewhat proportional to the temperature of the actual processor. The current flowing through this diode is compared to the current flowing through a precalibrated circuit (this is what defines your threshhold temperature where throttling will occur). That's how the processor determines if it's getting too hot. Whoever wrote that article is flat out and simple on crack. It has nothing to do with the power usage on a processor... it has to do with cooling. Provide enough cooling and you wont' have to worry about it and you'll be able to run your processor right up to the full 1.5 GHz(and probably then some). This is more for the el-cheap-o mom-n-pop shops that can't actually validate their designs and just slap a metal heatsink on their processors and call it good. Thermal throttling is not a new idea .... the mobile market has been doing it for years. The mobile Pentium II has a thermal sensor on it too (ftp://download.intel.com/design/mobile/applnots/2 4372401.pdf) however back then the throttling mechanism was implimented outside the processors. Now that they can get small enough, they just migrated it onto the die itself. Would you rather your machine just turn it self off like everything else when it overheats? Or worse not do anything at all and just toast it self?

Re:And what will the wider consequences of this be (1)

alen (225700) | more than 13 years ago | (#288647)

Yeah, and my Commodore 64 was all the speed I needed. That 2GB HD I bought in 1997 was all the storage I needed. And coe to think of it that 80MB hard drive that the teacher in my 8th grade computer lab had was the bomb. I wanted one so bad it was worth the $500 price tag. It would last me a lifetime. I mean who could ever fill up 80MB?

Re:is there some reason? (1)

jrockway (229604) | more than 13 years ago | (#288648)

We all love Debian/PPC!

Good heatsink (4)

DaSyonic (238637) | more than 13 years ago | (#288650)

This wont happen if GOOD heatsinks/fans are used. These processors get hot. I wish AMD did this, as AMD is smokin. But for the price, you cant argue on AMD. Though many AMD users have either burnt or cracked their chips, so having protection like this isnt always a bad thing. just use good heatsinks and you'll probably be just fine and dandy.

my god! (1)

Beowulf_Boy (239340) | more than 13 years ago | (#288652)

Not only is this Heatsink on that thing the size of a fridge, now they tell us its not big enough!
Well lets just strap a box-fan on the side of the thing!!

Re:Half Speed, Half Price (1)

crankie (243627) | more than 13 years ago | (#288653)

"Because it runs at half speed half of the time"

Wrong. It runs at full speed half the time. And at nothing the other half. If it ran at half speed half the time, depending on what it did the other half of the time, it could be anything from 25% to 75% efficient.

Re:And what will the wider consequences of this be (1)

megaduck (250895) | more than 13 years ago | (#288654)

I expect that we have reached the end of computing history. Things do not move forward now, and computers do all we need them too.

Nice troll. True, Moore's law may eventually break down, but it seems ridiculous to say that hardware innovation will stop. People have been saying this kind of thing forever:
In 1899 Charles Duell (Head of the U.S. Patent Office) said, "Everything that can be invented has been invented."
In 1981 Bill Gates said, "640K ought to be enough for anybody."
In 1996, John Horgan (Senior writer for Scientific American) wrote a book called "The End of Science?".

Invention slows down sometimes, but it never stops.

Re:This has always been a problem (3)

kbeast (255013) | more than 13 years ago | (#288656)

That may not be too good either. Having too many fans can cause bad circulation pushing air back and forth to each other, doing nothing at all. Check out a pic at this site [compute-aid.com] towards the bottom how "ATX Standards" show how to cool off the system...

Honestly, Out of the two types of cases I have, I have a In-Win Q500A and two Enlight Cases (Full and Mid-Tower), the Enlights stay super cool, the panel is always cold to the touch, the In-Win burns up on the side...I love my Inwin case though...its just always HOT..

.kb

This is not bad (5)

DivineOb (256115) | more than 13 years ago | (#288662)

Come on people... you even made me log in to reply to this one... This is not a bad thing, but a good thing. Power has been a problem for cpus for a while. This is, in fact, actually a quite cool feature. Generally how processors are designed is you get some guy to generate the maximum heat producing code that he can find. It doesn't do anything useful, and generally consists of lots and lots of floating point instructions. Then, you find out how much this heat this program generates when run on your processor. Now, you design your processor to be able to tolerate the heat generated by this program. However, first of all, no program that does anything useful will ever generate as much heat as this test program. SO really, you're forced to design your processor packaging for a way overkill case just to be sure that you don't have your processor die when someone is doing legitmate work with an unoverclocked processor. It has been shown that packaging costs increase by about $1 per watt generated by a processor for every watt over $30, so you can see that developing your packaging for the worst case scenario can be quite expensive. The alternative, then, is exhibited in the P4... Build your processor packaging for less than the worst case, then use some form of thermal throttling to prevent overheating. This has two advantages 1) It lowers your packaging costs 2) It prevents processor death in the case of catastrophing failure (such as a fan dying). I expected that people would get up in arms about this feature, but really, most of you just need to learn about the most recent research in this field to see this is actually a step in the right direction. However most people on slashdot are primed to jump on Intel at every opportunity, so they interpret this in the worst possible light. And BTW, I'm getting my PhD in computer architecture, so I know what I'm talking about :P. There have been papers at all the major conferences for the past few years dealing with power issues, and I might work on one myself soon.

valid? (1)

IanA (260196) | more than 13 years ago | (#288663)

OMG I found a post on a message board!! I think all of slashdot should be told!!

talk about bad reporting..

Half Speeds (1)

Husaria (262766) | more than 13 years ago | (#288664)

Usually they say processors won't really reach their highest speed. But half of the highest speed? Come on! Should I buy dual processors to have the speed of what one is? AMD looks better and better.
I wonder what over clocking would do

Re:Morons.. (2)

markmoss (301064) | more than 13 years ago | (#288665)

Yes, it is a good thing that the chip throttles itself down instead of melting down when it gets too hot. And apparently (contrary to the article), it won't throttle down if it has enough cooling. The issue is that Intel's specs are misleading as to what constitutes enough cooling -- they say 53W, but to actually get all the computing power you paid for, you need a 73W heatsink. It's like advertising a car as capable of 150 MPH and 50 miles to the gallon, but burying in the fine print that you get that gas mileage by turning off the V8 and running 10 mph with a lawnmower engine.

Re:I couldn't imagine a P4 at half speed... (3)

markmoss (301064) | more than 13 years ago | (#288666)

I guess my P60 would kill at Pentium 4 750mhz. It's not that bad, by almost an order of magnitude -- that is, you'd need a 500 or 600 MHz chip to beat the throttled down P4. And it only throttles down if your cooling isn't good enough. But the main point is, unless your software has been recompiled specifically for the P4 (and I don't know if there are compilers that will do that yet), the P4 will give you less performance for more cost as compared to the 1.2GHz AMD. The release of the P4 in its present status seems very premature...

DOS / 4 ? (1)

Hormonal (304038) | more than 13 years ago | (#288669)

OK, it seems, that if this makes your processor run half-speed, half of the time, and full speed the rest of the time, your CPU would run at 3/4 its advertised speed.

Would it be possible for someone to write a piece of software (running on Windows, of course) to send this PROCHOT signal (or otherwise trigger it), regardless of the processor's actual temp?

If so, that would seem like some sort of 1/4 denial-of-service attack (assuming a denial-of-service atack consumes all available resources, rather than just making a system sluggish.)

I'm not good with low-level things, so I have no idea if there's any way to send this PROCHOT signal at anything other than a hardware level. If someone could clarify, I'd be grateful.

So use a real heatsink! (1)

abumarie (306669) | more than 13 years ago | (#288673)

I'm not a real fan of the P4 (as you all may have noticed), but this is an issue of getting sufficient cooling to the chip so it stays within spec. I have a couple of cooked T-Birds for tie tacks that would have benefited from this technology.

Quote from elsewhere.... (1)

Anemophilous Coward (312040) | more than 13 years ago | (#288674)

Sorry cant remember the original owner, but it was from an article linked to from here when this story was ran last week:

"1.5Ghz. It's there. Except when you need it."

hype. (2)

thopo (315128) | more than 13 years ago | (#288676)


that sounds like why-your-intel-processor-is-bad-hype to me.
you may want to read this posted on hardocp.com:
Hi Kyle, You can run benchmarks all day on a Pentium(R) 4 processor with the benchmarks unaffected by the thermal protection circuitry. The key is to have a robust heat sink and thermal solution. With the heat sink setup we designed for Pentium 4 processor systems, I have yet to see thermal protection kick in. George.
(George = Intel PR George Alfs)

And here is a small excerpt from Kyle's comment:
We have been running an over-volted overclocked Pentium4 with the factory heatsink installed now for some time. It has been running here beside my desk folding proteins for Stanford University now for a solid month and has stayed at 100% CPU utilization. I track its performance and I can assure you that it has not ever slipped into the throttling that Bert speaks about above.

Mod this down please. It is just porn. (1)

geoswan (316494) | more than 13 years ago | (#288677)

It is a porn site. It has nothing to do with computers.

Re:Read up on the battle for the Tigris marshes (1)

modman (321805) | more than 13 years ago | (#288679)

I am sure those marshes were not worse than those found in nam, and the SEALS kicked ass in nam....the VC and NVA were teriffied of them, is a SEAL group was in the area the NVA knew that they were dead.

Re:Good heatsink (1)

modman (321805) | more than 13 years ago | (#288680)

sounds to me as if you have a 5600 rpm hard drive running off a DMA 66 controller.

disk access is the slowest part of the computer so if you want fast access get a 10000 RPM SCSI hard drive :)

Effecient engineering (3)

Peter David Bailey (325360) | more than 13 years ago | (#288681)

Props to Intel! What a way to keep their system in shape! Heat sinks and fans are already at the highest level of heat displacement they could possibly get. Fans have not evolved for decades - they've only gotten bigger. With normal methods of heat displation, Intel needed to find a new way to get rid of the excess heat the P4s create, and what better way than to have them alternate their cycles as on/off? Sure, you might only get half the clock cycles, but the ones you do get, are two times faster, so you are getting even more performance than a regular chip! I can see this coming into wide use in the server market, where most caculations are quick file access requests, because the average user doesn't need pure horsepower ontheir file server, they need faster disk speeds. I think this new design might also save some power in West, where the bulk of those machines will be bought and used. Then, the other west coast states such as Arizona, Nevada, and Texas can sell their extra power to California. Keep up the innovating Intel! I can't wait to get myself a dual proc p4!

Re:my god! (1)

dhamsaic (410174) | more than 13 years ago | (#288683)

i did that one time. the fan in my power supply died and i didn't want anything to overheat, so i took the cover of the case off and set up a box fan right beside it. kept the system nice and cool :)

Like this is old news? (1)

GearheadX (414240) | more than 13 years ago | (#288684)

We've known all about the creative malfunctions of computers when they get hot for years now, this is nothing new. But I'm not sure I'm too keen on the thought of something resident in the hardware throttling the rating on the processor when it overheats.

That's what extra fans are for...

quantum bogodynamics /kwon'tm boh`goh-di:-nam'iks/ n.

A theory that characterizes the universe in terms of bogon sources (such as politicians, used-car salesmen, TV evangelists, and suits in general), bogon sinks (such as taxpayers and computers), and bogosity potential fields. Bogon absorption, of course, causes human beings to behave mindlessly and machines to fail (and may also cause both to emit secondary bogons); however, the precise mechanics of the bogon-computron interaction are not yet understood and remain to be elucidated. Quantum bogodynamics is most often invoked to explain the sharp increase in hardware and software failures in the presence of suits; the latter emit bogons, which the former absorb. See bogon, computron, suit, psyton.

- From the New Hacker's Dictionary


Berk Watkins

Re:This has always been a problem (1)

Tech187 (416303) | more than 13 years ago | (#288686)

Unless you know what you are doing, all you end up accomplishing is messing up the air-flow that the case designer intended. This can have the end result of reduced cooling. Using a fan to blow in and another fan to suck out of the case can have this effect, particularly if the two fans don't have the same volume, and those are the only two openings in the case.

But all bets are off with most cheap 'clone' cases anyway.

The more fans the noisier the machine will be, though, which should also be a consideration before over-fanning your box.

Re:Like this is old news? (1)

Tech187 (416303) | more than 13 years ago | (#288687)

No.

Extra fans are to keep it cool enough that the 'throttle' doesn't kick in.

If the throttle didn't kick in the chip would burn up. That's what happens with AMD chips.

In a properly designed system the processor should never get that hot.

Re:is there some reason? (3)

Tech187 (416303) | more than 13 years ago | (#288688)

Motorola makes the StrongARM processor???

Half Speed, Half Price (1)

TheRealKennRoss (443630) | more than 13 years ago | (#288693)

"tells the processor to switch itself on/off 50% of the time until it's temperature is within Intels spec-range again." maybe that's why Intel said it might cut the price of P4's inhalf. Because it runs at half speed half of the time.

Wait, this isn't THAT bad (1)

rbgrn (443653) | more than 13 years ago | (#288694)

The real discussion of the thermal detection is discussed from page 22 to page 28 of the thermal guidelines document. They had a few interesting bits in there. For one, the thermister always works (you can always see how hot your core is) but the actual modulator is disabled by default. Now they do have specs that call for it to be enabled on any system pre-built, but for most techies, they should be able to disable it in the bios (provided the SMR is there) or it might need to be enabled somehow to work at all.
I can't say that this whole processor-limiting thing is terrible, I mean, there are reasonable ways around it (big heat sink, lotsa fans) and you actually have to opt-in to use it.
Also I thought I might add that 50% is NOT the hard number of cycles reduced, you can set that value to whatever you want the cool-down duty cycle to be (see page 24-26).

-Rob
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