SP-94 and very high load temps ???

[photogearjunkie]

I just installed an SP-94 Heatsink, to replace my Swiftech MCX4000. I am using this to cool a 3.0C (running at 3.6) on an ABIT IC7-MAX3. I'm using a 92mm Thermaltake smartfan, at 3000rpm, pushing about 52cfm of air. The temps that I'm now getting are only 1 or 2 degrees better than the Swiftech:

Idle temps after 1 hr:

MB: 27degreesC
CPU: 42degreesC


After 1 hr of dual Prime95:

MB: 30degreesC
CPU: 60degreesC


I have PLENTY of air running through my case (over 65cfm, intake=outtake). I know that the ABIT reports higher-than-normal temps, but 60 degrees seems way high! I have installed/reinstalled this heatsink twice, checking to make sure that I'm getting perfect coverage for the AS5 (which has already passed the 200hr burn-in).

The only thing I can think of is that the base wasn't finished properly. When I ran my finger nail over the base, I could hear a very faint 'zippering' sound. Also, the machine marks are faint, but definitely visible. I applied a light coat of AS5 to the bottom of the HS, and then used a credit card to remove it and see if any AS5 remained in the valleys between the ridges. However, the credit card seemed to remove everything??? Which doesn't make sense, since I know there are ridges by the sound my fingernail makes when it's run along the base of the HS. (And I don't feel like I should have to lap an already expensive heatsink, either! This is one area where Swiftech has always been second to none!)

I would really appreciate any advice, since I'm very confused.

Thanks!

 

[PCTweaker5]

Does the HS feel very hot when its at 60C or just slightly warm? If only slightly warm then the heat isnt being transfered very well. I suggest turning a plastic bag inside out, rubbing the AS5 in a circular motion over the base and then wiping it off with a paper towel and you should see the blurriness of the ridge filling. And if the SP94 uses the MB holes then make sure that you tighten them in a criss cross pattern so that it is evenly touching the surface and tighten the screws until they stop turning.

 

[Cerb]

What PCtweaker5 said.
The base not being well finished isn'tgoing to make that much of a difference. Really. You've got a IHS on there, which basically kills all your lapping benefit.

 

[photogearjunkie]

I did install both the SP94 and AS5 exactly according to their directions...twice, since I wanted to figure out what the optimum amount of as5 is, to make a perfect circle that coves most of the CPU. I'll do the finger test to see how hot the HS is during testing.

What is an 'IHS'?

Thanks!

 

[Cerb]

Integrated Heat Spreader. The silvery thing on the chip that covers the die. It has thermal adhesive under it attaching it to the core itself. Through that, you lose some cooling potential. It's there so you don't chip the core, like you can on PIIIs and Athlon XPs.

 

[PCTweaker5]

So exactly what kind of thermal paste do they use under heatspreaders? Is it just plain old white goo or some high quality stuff like AS5? My 5950 Ultra has that heatspreader too and wish it was just the core alone but my temps are still pretty good so Im not gonna go taking it off I just want to know what they use.

 

[Cerb]

Cheap stuff. Remember, they are in the business of cutting costs and not letting it overheat, not getting that extra 2C in CPU temp. Don't be taking the IHS off...I've seen a few pics where somebody tried and ripped the die off the packaging!
For normal cooling, AS is overkill. When you spend $30 or more for a heatsink, it doesn't seem so bad, and Ceramique is worth it just for ease of application, but overall, it'd be a major waste of their money (and then cost you more) to use nicer TIM.

 

[PCTweaker5]

Originally posted by: photogearjunkie
I did install both the SP94 and AS5 exactly according to their directions...twice, since I wanted to figure out what the optimum amount of as5 is, to make a perfect circle that coves most of the CPU. I'll do the finger test to see how hot the HS is during testing.



What is an 'IHS'?



Thanks!

I love your sig man!