Originally Posted by SaTaN0rX
you can underclock the card using the nvidia-settings utility
you need to set
Option "Coolbits" "1"
in the device section of your xorg.conf to allow over/under clocking
And then? I have this option set (already for several versions of the driver) but I cannot figure out what to do in nvidia-settings. It allows me to set the sync options, color settings, sharpness etc. And it shows the temperature. But nothing related to clockspeed.
I, too, think the card is running too hot. Mine is always above 70 deg C. In this hot summer it sometimes is above 80.
This is partly due to the stupid fan design of the card (it takes in air from the place where the next card sits), but it also seems that this particular model (6600GT) dissipates quite a lot of power.