I've just recently bought a used computer. It's an hp p6803w. It has a amd athlon II X2 220 processor 2.80ghz, 4 gb of ram, and a ati radeon hd 4200 graphics card. I'm wanting to run games on it. I don't know much about computers, and what would be compatible with mine. I have league of legends and WoW right now. They both run at 60 fps on the lowest graphics setting, but i'd like to be able to play on at least medium. It would be nice to be able to run Dayz eventually too. i'm not positive where to start, but i'm open to any suggestions. Any good graphics cards for under 100$, and what else should i upgrade for gaming? And I don't mind buying used.