SpeedFan shows my 8800GTS is burning up at 88-90C - I'm just browsing the net right now nothing special. Does anyone know how to possibly adjust the temperature (besides buying water cooling). I don't think 88-90C is normal lol
I should qualify the last comment on replacing the heatsink and fan, some manufacturers allow you to install 3rd party cooling solutions without voiding the warranty, so long as you keep the stock one, and reinstall it prior to returning the card for repair/replacement.
Sounds like a case of the dust monsters.
Take the card out and check the fan, if it looks clogged with dust or fibre the heatsink fins will probably be choked as well. I think you only need to take 4 or 5 screws out of the top cover to expose the heastink itself but be warned, they are very small screws so use a good screwdriver or you risk damaging them.
I just had a similar situation for a 8800GT. The problem was that the driver was not kicking the fan speed up while under heavy use, ie. gaming. The quick fix is to use nvidia control panel and manually set the fan speed to a higher level. The default was 30%. When the fan speed was changed to 70% the GPU cooled down quickly. Let us know how you make out.
I tested Speedfan, and it was bang on with EVGA Precision, and Everest, and Riva......
Now as far as CPU temps, and voltages, it definitely has issues.
Again, like Myself and other people have stated, blow out the dust, preferably with an Air compressor since it has more oomph than a can of air. Also I recommend removing the card from the case to do it.
Did you happen to check if the fan was even working?