I have a Compaq Presario CQ5500 that I'm upgrading. I already bought a 600W PSU, and will be upgrading my RAM and getting a new CPU soon, probably at Phenom but at least 2.6 GHz Athlon. What graphics card will work with my system for gaming? I'd like a few options, both budget and a the best option available. I'll probably buy a budget one first and then upgrade to a better one once I save up enough money. I bought a Radeon 6450 but I know its not the best for gaming.