With games like Oblivion not so far off, its time for me to consider an upgrade. I want to know whether or not its worth upgrading to a x850 XT or 6800 GS (for shader 3.0 support) from a 6600, or would the performance boost not be good enough to warrant the price? Ive thought about getting a pci express compatible board, but then Id also have to buy a new cpu on top of that and a card that'd end up costing more than I think I'd really want to spend. So, is upgrading to a x850/6800 gs worth it when I've got a 6600? And, if so, would I really be better off with a x850 and not having the ability to use newer features with with the 3.0 shaders or having the 6800 gs and having alittle weaker performance? I'd appreciate what feedback anybody has to offer.