Hi, I've had my current PC for just over 2 years now and I'm thinking of upgrading my graphics card. When I bought my PC it was a high specification for the time but it's started to struggle with some of the latest games. My Current system is Intel i7 processor @ 3.6Ghz, Nvidia Geforce GTX 580, 12GB RAM, 2TB Hard drive. I don't actually know what the Power Supply is in Watts (opened it up and cant find it anywhere) and I don't know what motherboard it has etc so I'm wary about buying any new hardware for it until I know it will work. Unfortunately I bought one of those ready made PC's from PC World (Chain shop in the UK) which meant I could only overclock it an extra 0.4 GHz or something rather pointless. I've heard the 580 was a fairly powerful card which needed a lot of power so I'm thinking the Power supply should be good enough? If a normal person saw my PC they'd think I could run NASA on it because it's HUGE but that doesn't necessarily mean it can power a card 2 years into the future. I don't know any advice? Also how much more performance would I get if I upgraded from a 580 to 780? I wouldn't really upgrade if I'm only going to get a couple more FPS.