is it possible to run a Radeon HD 4870 with my current rig? i dont know if there is enough power from my psu. How much do these cards take? my rig is in my comment. im just looking for a good upgrade from my nvidia 6600gt. I thought about doing 2 4850's but i think its more bang for the buck on the single 4870. let me know if im wrong. what would you guys suggest? thanks