New Heatsink Needed?

group6

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May 20, 2008
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Pentium 4 HT LGA775 3.4GHz on Asus P5AD2 deluxe mobo. Getting overheat messages. Ran Asus pc probe, getting CPU temps of 71C to 74C. Intel recommends no higher than 70C. Opened the box, cleaned all the dust out with canned air. Heavy deposits on heatsink/fan. Still getting temps too high. 80mm case fan in back, 80mm Tornado fan in front, stock Intel heatsink/fan that came with CPU. Case has an intake 'scoop' that is situated over CPU heatsink/fan. It actually runs cooler with the case closed. Box has been running set up this way for years.

I replaced the original stock Intel heatsink/fan with a new stock Intel heat sink/fan. (Intel Stock Pentium D Radial Curved non-Bifurcated Fin Heatsink)

No more overheat messages. I checked the BIOS, the CPU Q-Fan control which enables PWM was not enabled, I enabled it. The hardware monitor control stated a target temp for the CPU was 66C. At boot, room temp was 28C. CPU went up to 72.5C with the fan RPMs from 1371 to 2960, fan spec 2600RPM. I turned PWM off and it still was running at variable. Booted the OS. The Asus PC Probe was telling me the CPU temp was in the 50s. So much for the Asus PC Probe. Intel states that the "thermal design Power" load is 85W and that the "thermal spec" was 67.7C. When I looked at the Frosty-Tech review for this HS/F, the testbed temp was 33.8*C (temp above ambient). 72.5C is almost twice the test results. The probe and the mobo monitor both showing showing something different.

A lot of discrepancies here. Typically, is either temp app reliable?
Why the discrepancy b/t the probe and the hardware monitor?
Whats up with the PWM?
Why such difference b/t my temps and the review temps?
Should I get another HS/F to cool it further or is this sufficient?

 

the last resort

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Apr 13, 2008
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The Asus PC Probe worked for me, but i did not like it too much.
If the heatsink/fan is a 4-pin power, even if you turn on PWM you will not have full control when using the 4th pin. In my motherboard, (M2N-SLI-Deluxe) If i turn down the CPU fan all the way in Speedfan, "0%" is about 1000 RPM. And if i want to turn it to max "100%", that is about 3100 RPM. THe fan on the heatsink is rated for 6000 RPM. The reason is because it is temp. controlled.

It also sounds like their is not enough air flow, with only 2 80mm fans. If possible, may want to replace the back fan with a higher CF/M rating, like the tornado. And yes, a new cooler wouldn't hurt anything.
 

group6

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May 20, 2008
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Thanks for the quick reply. It is 4 pin. So with PWM enabled, the fan acts the same as PWM disabled because it is strictly controlled by the CPU temp. I could replace the 80mm rear fan with a 92mm 119CFM Tornado; It sounds like an F-117 at take off. That might do it. $13 for that fan or say, $33 for a Scythe Shuriken (need reduced height because of the induction clearance) Or both-anything worth doing is worth overdoing.

Where do I find speedfan?

I wonder why the HS/F tests are so much cooler than what I get.