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Is Your P4 Working At Half Speed?
"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.
Well lets just strap a box-fan on the side of the thing!!
Hehehe looks like someone did..
Your Working Boy,
- Otis (GAIM: OtisWild)
No, reading Slashdot isn't THAT taxing on my cpu.
Unless you're using Mozilla.
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.
In case of Emergency, Curl up in the Fetal position, and lick a Bible for comfort!
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.
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.
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I like to watch.
This story was posted and discussed at length 3 days ago...
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.
Linux: Because a PC is a terrible thing to waste.
James Brents
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.
I must burn in hell, suffer and pay for my sins
But Gods the one who's losing, Satan always wins!