AHA!
watson i think ive done it
elementary my dear, elementary....
they may look the same but the reason the gigabyte one is more expensive is because it has ViVO (Video in Video Out) what vivo allows you to do is things like hook you standard dvd player up top your tv, or if your like me... play Xbox on my LCD monitor, oh goody. thats what vivo does, you can also record the things coming through vivo, and vivo also puts a signal out too, aka tv on bigscreen. But if you dont want vivo then go with powercolor. if you do, go with gigabyte.