I have my radeon 4850 overclocked from 625mhz core and 1986mhz ram to 690mhz core and 2250mhz ram(i just used the auto-tune feature with the catalyst control center that came with the card and rounded up). I tested it out with oblivion and everything is running great, except for the occasional artifact. In my mobo's bios there is a voltage adjuster for the pci-ex slot, and i want to know if that would help the card have less artifacts, and if it would let me reach a higher overclock. The fan is plenty to overclock more, at 40% the gpu maxed out at 72*C. The voltage adjuster works just like the one for the ram, so im just wondering if it lets you push the card further, as you can with ram. If its really a bad idea to play with that, then i can always back down on the overclock and see if a higher fan setting could stop it.