Videocard overheating

So I have an X1900, but I found that the stock fan was way too loud. So I replaced it with a Zalman VF900-CU

I believe I installed everything correctly, however I am getting very high temperatures.

My Idle GPU temps hover between 55 and 60 C. Under load (Crysis Demo) it will spike past 100 C at which point I shut it down. I made sure that there is no dust in the case, on the card, or in the heatsink. I’ve also verified that the fan on the Zalman is working. I’m also not overclocking.

I have good airflow through the case, even putting my case fans at close to 100% speed. Could it be that I improperly applied the thermal grease? Could the thermal grease make such a difference? The only thing I can think of is that the Zalman heatsink isn’t coming into contact with the chip, but I really don’t know. Any suggestions?

You might want to clean everything up and check to make sure that the heat sink is actually making good contact. Make sure that you apply a GOOD thermal paste like Artic Silver or their Ceramic version. The main secret when applying this type of compound is to use a razor blade and make “Waves”. This allows the air to escape as you seat the chip.

IIRC, temps slightly under 90 C are par for the course with that videocard. Did you bother checking the temperatures before replacing the cooler?

Thermal paste application is the place where most people mess up a heatsink installation. I would redo the installation, making sure you’re following proper protocol for thermal paste application.

Don’t bother spreading it around, you’re more likely to contaminate the paste than you are to create a more even mound of paste. Just let the pressure of the heatsink spread the paste on its own. Too little is preferable to too much, in my opinion, so my rule of thumb is 3/4 a grain of rice for a typical 1 square inch chip.

It needs to be said the paste should be very thin. Did you properly clean the old thermal paste from the stock HS?

Isopropyl alcohol, the higher the better. Never use rubbing alcohol (compounds can be left over). If it was a thermal pad you’ll probably want to use acetone then alcohol to remove the acetone. Google for techniques.