Re: Overclocking the 6800GT...
When you talk about bumping the voltage in your system's BIOS, that is not bumping the voltage that the video card core is using, it is setting the voltage for the AGP slot. To change it on the card, you need to mod the video card BIOS. 6800GT card were notorious for not liking higher voltages than stock, so that is likely not going to help you. You are really running a pretty good OC for a 6800GT at the moment and I doubt another 5 or 10 Mhz is going to do anything for you in modern games. You just need to run low resolution with no AA and only light AF to play modern games on that card. I must say thought that I certainly got alot of mileage out of mine, and there is still one in my wife's rig.
As far as bumping the AGP slot speed; well that is not really what is limiting you so I would leave it as you have it. Once you hit 83 you are going to start looking at instability issues. I always found 75 as a good stopping point.
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