I wanna build a bedrooom pc out of leftover parts..(Athlon x2 5600, Radeon 2600xt 256meg, ECS AM2 mb, 2x1gb Crucial Ballistx DDR2-800 ram). I'd like to do the usual HTPC stuff with some social networking and light 720p gaming thrown in. Just wondering if I should run Win7 or downgrade to XP. My other computers have win7 on them but have more memory. I don't wanna buy any new parts, just make the best out of what I have. Motherboard only has 2 slots so I'd have to buy new 2gb sticks to go up to 4.