How long does a thermal paste/grease last for Intel P3 CPUs?

In comp.sys.ibm.pc.hardware.systems wrote:
> In comp.sys.ibm.pc.hardware.systems George Macdonald <fammacd=!SPAM^> wrote:
>> On Sat, 16 Aug 2003 08:17:03 -0000, wrote:

[...]
>> still have my retail PIII 450 and it runs at 65?C on a warmish day - say
>> 25-30?C room ambient. I've never touched the thermal grease on it because
>> it looks like it is still a paste - the stuff that I can see anyway. The
>> lower cost thermal pastes *do* tend to separate out and bleed the
>> oil/grease away, particularly for the cache chips which do not actually
>> make direct contact with the heatsink plate - IOW the thermal paste
>> actually fills an air gap.

> That is what happened last time. I am thinking the grease fell apart
> again. I don't remember what brand I used last time since it was almost
> a year ago or so. Which brand do you suggest? I live in Southern CA, USA.

That should not happen. Thermal grease only works well when there
is no air-gap and the surfaces are pretty smooth. Otherwise
you need to use a thermal pad that has worse thermal conductivity
but is designed to bridge a gap, i.e. will work for a longer time
in this situation. Also you have to use a pad of the kind and
thickness.

The problem is that if there is any significant gap, the grease will
dry out and shrink, which makes it ineffective. You cannot correct
this problem with better grease.

Arno
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On Wed, 20 Aug 2003 04:07:47 -0000, wrote:

>In comp.sys.ibm.pc.hardware.systems George Macdonald <fammacd=!SPAM^> wrote:
>> On Sat, 16 Aug 2003 08:17:03 -0000, wrote:
>
>
>> mbrd monitors are not a good measure due to calibration differences. WHat
>> you need to look at is relative temps: working vs. not working?
>
>The BIOS and softwares were the identical. Right now, almost idled
>temperatures 98.6 degrees(F)/38.0 degrees(C) with:
>load average: 0.12, 0.17, 0.11 ... Not working temperatures were listed in
>my original posts. I don't want to compile or do anything intensive to crash
>again. The system has been up for 2 days so far, pretty much idling.
>
>Before the problems came back up from my compile, I had 160+ days uptime.
>Darn it. :P

I'm not sure if your mbrd is measuring the CPU temp using the on-chip diode
or an external probe but 38C is really very low from my POV. My PIII/450
runs at 60-65C in a P3B-F, depending on ambient.

>
>> Was that CPU a retail version with the Intel installed heatsink/fan? I
>
>Yep. Retail with the goodies.
>
>
>> still have my retail PIII 450 and it runs at 65?C on a warmish day - say
>> 25-30?C room ambient. I've never touched the thermal grease on it because
>> it looks like it is still a paste - the stuff that I can see anyway. The
>> lower cost thermal pastes *do* tend to separate out and bleed the
>> oil/grease away, particularly for the cache chips which do not actually
>> make direct contact with the heatsink plate - IOW the thermal paste
>> actually fills an air gap.
>
>That is what happened last time. I am thinking the grease fell apart
>again. I don't remember what brand I used last time since it was almost
>a year ago or so. Which brand do you suggest? I live in Southern CA, USA.

I haven't bothered with any of the exotic heatsink compounds, like Arctic
Silver et.al... so I can't recommend anything from experience but it might
be worth trying for you.... or as previously noted, the AMD recommended
phase change stuff.

Rgds, George Macdonald

"Just because they're paranoid doesn't mean you're not psychotic" - Who, me??