So im debating on getting a alienware x51 (dont try to talk me out of it im only thinking about it.) it'll have an i5 4430 cpu and a gtx 645. i want to upgrade the GPU to a 760 but i dont know if the 330W powersupply will be enough... will it be enough to power a i5 4430 and a gtx 760?
Yes the x51 can power the i5 and gtx 760! If you look on there site they sell it with the i7 4770 and the gtx 760, same power requirements as your setup would be. The alienware x51 doesn't use as much power as a typical PC. Here is a break down.