Hello i'm looking to upgrade to a 2GB ASUS GeForce GTX 680 DirectCU TOP GPU and i was curious as to if this card consumes more power than a reference gtx 680's 550w minimum . I am currently running a 620w SeaSonic power supply. Would I be able to run this card? Also will 2GB's of vram be enough to support single monitor gaming for the next 2-3 years? Or would it be a better idea pick up a 4GB version of a gtx 680 to be safe and further future proof my graphic card? Is there another 2GB/4GB version of a GTX 680 you would recommend? Thanks in advance!