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View Full Version : How much thermalpaste on the GPU?


Soetdjuret
05-27-08, 12:12 PM
Hello, i never seem to get this right. My 8800gtx is ideling at about 70 degreeds celcius. I open the card remove the cooler and look if the thermalpaste is covering the whole gpu together with the cooler and it does, looks like i have full contact between them. Now i dont know if i should add more paste or remove to make a super thin layer? How thin is the layer supposed to be? Or is it something else i am doing wrong?

Many thanks!

Soetdjuret
05-28-08, 07:46 AM
Help please?

BCKator
05-29-08, 12:55 AM
Has it always idled this high?
In general, you want the paste as thin as possible.
I would recommend cleaning it all off, reapplying a thin layer, assemble, disassemble, check for contact patch, and then, once you are sure or your technique, do the final assembly and re-test.

bobkn
05-29-08, 10:51 AM
Traditionally, you want the thermal compound to be as thin as possible while filling the gap between the heatsink and the GPU.

However, on my eVGA 8800GTX, mechanical clearances do not permit the use of a thin layer. When the mounting screws are tight, there is a gap between the heatsink and the chip. (If memory serves, it's not the actual silicon but a metal heat spreader.) The factory's thermal compound was applied quite thickly, and I had to do the same. I didn't explore modifying the card or heatsink.

The gap between the heatsink and the memory chips was worse. I replaced the pads (fabric saturated with white thermal compound) with polymer pads, nominally 0.5 mm thick.

My 8800GTX also idles at around 70C with the factory heat sink and fan, even with the new thermal material. That's with the core and memory clocks set at base 8800Ultra levels (612/1080 MHz).

For a time, I used a Thermalright HR-03 Plus. I don't recall the temperatures it gave, but I believe that they were lower. However, that seemed to have no significant effect on the overclocking potential of the card. The card with the HR-03 Plus occupied 3 full case slots, and I didn't care for its cooling of the card's memory. (That was small aluminum sinks, stuck to the chips with thermal tape. One of them was always falling off, even though I cleaned the chips before applying the sinks.)