baxben7
[07] Duelist
The GTX 680 would be better. You can use these links to compare the two cards.
GTX 680 http://www.geforce.com/hardware/desktop-gpus/geforce-gtx-680/specifications
GT 630 http://www.geforce.com/hardware/desktop-gpus/geforce-gt-630/specifications
But you will need a good power supply to have that GPU.
GTX 680 http://www.geforce.com/hardware/desktop-gpus/geforce-gtx-680/specifications
GT 630 http://www.geforce.com/hardware/desktop-gpus/geforce-gt-630/specifications
But you will need a good power supply to have that GPU.