Idle temp isn't too bad, I run a G92 Core 8800GTS, specs wise aside from total Memory & Memory Bus Width, its pretty much the same as a 8800GTX (different clock speeds also), just based on the more efficient G92 core instead of the older G80 core.
Idle, my card sits at 67C, I checked the nVMonitor app in the nvidia control panel, & checked the GPU settings for the app, default setting for GPU Temp Thresh Hold is 127C... so even if he's running 90C, though thats pretty hot, its really not that abnormal.
compared to the 8600 series, the 8800 Series (G80, G92), & 9800 series, run a fair bit hotter than the lower cards, also have higher thresh holds as well. (Don't know if either one of you have seen the warning label on the 9800GX2's
, yeah gets hot enough, it warns you not to touch the metal parts of the card while its in use
)
have you made sure your card is cleaned out, dusted, & no dust bunnies trapped in the vent at the back of the card/case?
make sure DirectX is updated to the latest version. (though DirectX is released in versions like 9.0c, or 10.1 or whatever, Microsoft does periodically release newer updated revisions of those versions, so update that if it hasn't been for a while.)
It could be your PSU, you mentioned its carried you through 3 years now, could be showing signs of its impending DOOM...
not all parts are made to run forever, especially PSU's almost all fail eventually, just depends on the Quality of the unit, how long its been running/used, & other ourside factors.
make sure its cleaned out also.
What Brand, Make/Model of Power Supply is it?
whats its Ratings for 12V, measured in Amps, should be a sticker or something on the side of the Powersupply stating all this info.
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