i built my current pc about a year ago for 1200 bucks. that was everything from the case to the 22" monitor, and it's a micro-atx formfactor so some components were a little more expensive than usual. im sure the same or slightly better pc now would be about 900
it plays everything except crysis maxed out (60-80fps in oblivion maxed out, 90+ in bioshock, 70+ in COD4)
..and anyway... "low" on a pc game is about what the 360 and PS3 are doing.. so you're set for longevity
btw i have a geforce8800gts which i paid $350 for... the 8800gt @ $250 is supposed to be a hair faster(wasn't available when i bought mine)
..oh, and nvidia will be adding physics processing to all 8000+ cards through firmware upgrades soon.. so the possibilities will be expanding , giving the pc market another big boost over the console market(probably as big a boost as it had in ~1994 when we were already playing quasi-3d games like Doom online through 28.8kbps dialup connections

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