Dude, WHY are you posting in here??? This is the hardware QUIZ section. Gizmo when you posted your question, did you not see all the other threads titled "Hardware Quiz#....."?
Uhhh lone wolf...this isn't the hardware quiz section. This is the Hardware ZONE. So anyway Gizmo dont pay attention to him, he's obviously lost himself. Your question is kind of sparse so you need to do a little research and see what kind of processor you're looking to get, what kind of RAM, how much RAM, what kind of devices do you want to run, what kind of power supply do you have now, stuff like that. It was a perfectly reasonable question, just need to do a little more research