well, you can buy a really nice machine rate now for about nothing. Seriously, AM2 stuff is really cheap, you can build a machine that will be able to do anything you really want rate now for around $500 like a 4200 x2, 7600gt a couple gigs of ram(could save a little and just do a single stick) really nice board, 500w powersupply and get a cool case as well. If you want specifics i could put together a list, but thats just general stuff if you want to shop around yourself.
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Oh yeah, cool action games, oblivion is sweet, but its a little in-depth, fable the lost chapters, jade empire is sweet, balders gate, titan quest is good to, yeah and you should be able to pick any of those up for under $30 dollars to, oh yeah can't forget Morrowind, thats the sweetest, and you can run that on pretty much any machine.