   directx 10 and 64 bit systems...
  i recently bought call of juarez and i could never get the game to even install. it would constantly crash. so i took it back and got my money back. this is what im running right now. i havent had any trouble with fear, hl2, wow or guild wars.asus a8n-sli premiumamd athlon 64 32001.75 gigs of ram8500 gt 512 ram600w p. supplywindows xp 64 corporateservice pack 3   
  GameDev is not tech support.   