Will it be worth me buying a geforce 6600gt w/ agp bus for my old computer? I want it to be able to play some recent game titles like BF2, HL2, & Painkiller. It is for my brother and he wants to game, low resolutions are fine with maybe medium settings. Will this get him through one year, at which point he will build a new one? I have an Athlon XP 2200+ processor, 512 mb of pc2700 RAM (could probably upgrade to a gig, but MB doesn't support dual channel), a 250W power supply (likely have to upgrade it?), & some generic motherboard. Your input would be appreciated.