system temperatures still high after stress testing with Prime95
 

Just tried Prime95's stress test and my temps raised to around 95C for CPU and motherboard, and PSU 77C but when I quit Prime95 the temps didn't go back down (even blowing a desktop fan on high on the open computer case didn't help). I don't understand why the temps wouldn't go back down when CPU usage is minimal and Prime95 isn't even loaded anymore.

Even after a complete shutdown, unplug, and dust blowout (not much on the CPU heatsink), the CPU, motherboard, and PSU temps are still the same. WTF? All the fans are working fine too so I don't know what Prime95 did to screw up my system but SpeedFan and Hardware Sensors Monitor both give the same temps (and Speccy gives the same motherboard temp).

How could Prime95 have done this, if at all? And if not, what would be the cause since the temps were fine before I ran Prime95 to stress test my system??

A complete and total shot in the dark here, but perhaps you blew out the temperature sensors? :razz:

If the temps got too high for the sensors, it's plausible that they'd just keep sending the last correct temp before they died.

Hmm... what CPU?

You need to confirm that you did not do a normal install on Prime95 (this is my best guess). That would normally make it restart on boot and when you hit the X to close it, it just minimizes it to the tray. Try using the Start button to run Prime95 again, if it comes up and shows that it is already testing, that is your issue. You will need to either change the settings so that it does not start on boot, or go to the Test menu, hit exit, then you can delete or uninstall Prime95.

Seems I was dorking with the sensor types (diode, transistor, thermistor) in Hardware Sensors Monitor while Prime95 was running and didn't realize different sensor types give different results for some reason.

If I change sensors 1 or 2 to diode or transistor the temps are around 95C. If I change sensor 3 to diode the temp is 36C but with thermistor it's 76C. But what's odd is SpeedFan's temps are immediately affected, which I wouldn't think would even be related since both separate programs have their own separate sensor settings. I don't know what the temps pertain to either since, in HSM anyway, I can choose from different labels (CPU, CPU1, CPU2, M/B, PSU, Power, Chassis, Mainboard) for each sensor and the temp doesn't change when I choose a different label. (Some of the labels also seem redundant like M/B and Mainboard, and PSU and Power.) Anyway, I don't know what the temps are relating to but I can get the sensor back to what they were saying before I started dorking with them the same time I ran Prime95. I may still have an overheating issue but it's hard to tell now since I can't even trust the damn temp monitoring programs!

CPU is Pentium D 820 (2.8GHz) and I didn't do a normal install; just extracted zip and ran--it doesn't start with Windows either. Like I said, Prime95 was completely quit and not running yet the temps were still the same but it was because of Hardware Sensor Monitor's sensor types.

Damn, I wish intel would tell me the max recommended temps for their cpus... although I know over 80 is... high for any cpu.

The later generation Intel procs ought to be able to go past 85C, but yes, 80C is pushing it for any CPU. I don't know anything about the Pentiums though, but it seems like this one at least has a high tolerance.

[url]http://ark.intel.com/SSPECQDF.aspx[/url]

[QUOTE=Xyzzy;302836][URL]http://ark.intel.com/SSPECQDF.aspx[/URL][/QUOTE]

That shows you more than everything you need to know, except max temperatures.

Actually, TDP ([URL="http://en.wikipedia.org/wiki/Thermal_design_power"]thermal design power[/URL]) is the max temp. So my Pentium D 820 (BX80551PG2800FN) has a TDP of 95C degrees. I believe "Temp3" in Hardware Sensor Monitor's sensors pertains to the CPU and the other sensors are the northbridge (which has a heatsink but no fan--even blowing a fan on high speed against it doesn't seem to affect the temp reading) but I'm not certain. I could still have an overheating issue but not sure since I can play Crysis 2 on "advanced" graphics options fine without any freeze/hang/crash yet Oblivion and Fallout 3 have given me problems. See [URL="http://www.tomshardware.com/forum/338303-28-freezes-hangs-games"]this Tom's Hardware forum post[/URL] for more info.

Um... no. Absolutely not.

Power is a specific measurement which is completely different from temperature, and even then the Thermal Design Power isn't actually the maximum power that a processor can consume. Furthermore, just because one processor has a lower TDP then another, does NOT mean that it will be cooler. In particular, Ivy Bridge quad cores, despite having a 77W TDP, tend to [URL="http://en.wikipedia.org/wiki/Ivy_Bridge_(microarchitecture)#Heat_issue_when_overclocked"]run hotter[/URL] than Sandy Bridge quad cores, which have a TDP of 95W.

A Pentium D's TDP is 95[i]W[/i], not 95C. The former is a measure of energy per time, while the latter is (sort of) a measure of energy per entropy, entropy being (sort of) a measure of "disorder".

It's Thermal Design Power, not Thermal Design Temperature.

[QUOTE=Dubslow;303055]Um... no. Absolutely not.

It's Thermal Design Power, not Thermal Design Temperature.[/QUOTE]
The first and last line would have been enough, methinks.
"energy per entropy", and the rest of the sentence! Loved it! :popcorn:

Almost all of these new toys have a junction temperature of 100C, or even higher as 105C and 110C for mobiles (the reason is the mobiles lack big coolers, just now we are designing an industrial PC with i7 620M, whose J-temp is 105C, with passive cooling, no fans, just few aluminum blocks and heat pipes - the device is supposed to work well at CPU maximized in a 60C environment - this means room temperature. With preliminary testers we are well under 90C when P95 runs 4 workers, 2 phys plus 2 logical).

You can't fry these CPUs by running them at 90C, assuming you can constantly cool them and you don't have heat spikes which go much higher (this can not be detected by software like RealtTemp or so). New mobos have hardware which cut the power when the CPU enters thermal lock or throttle. The CPU is sending periodical signals to the mobo as long as everything is fine, independent of your software or OS. When the CPU is too hot and it enters throttling - all of the new CPU do this - the frequency of the signals to the mobo decrease. Clever mobos sense this and cut the power.

Asus will give you all money back if you can fry a (for example) Maximus Extreme by overclocking.

Are you saying it's fine to run them at 90C? I realize mobile cpu's can tolerate more heat, but I like to keep mine at about 50-60C (lower if possible)

[QUOTE=kracker;303119]Are you saying it's fine to run them at 90C? I realize mobile cpu's can tolerate more heat, but I like to keep mine at about 50-60C (lower if possible)[/QUOTE]
Not really. To keep the temperature as low as you can would be your goal. This will extend the lifetime of all your hardware, not only the CPU. See my older posts where I was talking about "bent plastic parts" and "fan blades deformed from heat" in 2-3 years on Sony laptops. Higher temperature shortens the life time of the hardware, not talking about additional energy consumption. In real life, with real tasks and real coolers, the temperature is never "constant". There are always up/down spikes which you can only measure with professional hardware, like in an electronic factories (I work in an one). To get a real feeling of what's happening, set the throttle=50 into prime.txt, and run for 10 minutes and look at the temperatures recorded by RealTemp. That is what some professional measuring device shows when there is no throttle and P95 runs at full capacity and RealTemp shows a constant temperature. Measuring equipment will always show oscillations of few degrees up and down even if when you think the temperature is constant. My point was: if you run your CPU at 90, for short periods of time you might have (undetected by the measuring software, which does averaging) 80, but you also might have 100. If you can keep the temperatures low, then better do so.

[QUOTE=LaurV;303177]Not really. To keep the temperature as low as you can would be your goal. This will extend the lifetime of all your hardware, not only the CPU. See my older posts where I was talking about "bent plastic parts" and "fan blades deformed from heat" in 2-3 years on Sony laptops. Higher temperature shortens the life time of the hardware, not talking about additional energy consumption. In real life, with real tasks and real coolers, the temperature is never "constant". There are always up/down spikes which you can only measure with professional hardware, like in an electronic factories (I work in an one). To get a real feeling of what's happening, set the throttle=50 into prime.txt, and run for 10 minutes and look at the temperatures recorded by RealTemp. That is what some professional measuring device shows when there is no throttle and P95 runs at full capacity and RealTemp shows a constant temperature. Measuring equipment will always show oscillations of few degrees up and down even if when you think the temperature is constant. My point was: if you run your CPU at 90, for short periods of time you might have (undetected by the measuring software, which does averaging) 80, but you also might have 100. If you can keep the temperatures low, then better do so.[/QUOTE]

Ah, I see what you mean. Thanks :smile:

[QUOTE=Batalov;303058]
"energy per entropy", and the rest of the sentence! Loved it! :popcorn:[/QUOTE]

At the risk of repeating myself,
Shannon asked von Neumann what he should call his new information theoretic expression.
"Call it entropy" came the reply.
"After all nobody knows what it means anyway"

David