|"Hi. I just wanna buy a new system (just graphic card , CPU , ram , power supply ).i already have case and hdd"|
So I guess you're going to use the same motherboard? There's no way we can make suggestions without knowing the make/model/specs of the board.
"I have 480w power supply. Do you think it's enough?"
Is it a $15 480W PSU or a $100 480W PSU? We have no idea if it's capable of handling a gaming system without knowing the make/model/specs of the PSU.
Have a look at this: $600 Gaming PC