Try not to use the power supply that comes with the case. Always get a better reputable one like from FSP(Fortron), Thermaltake, or Coolmax, because if your PSU fries then it can possibly take some components with it like your video card or motherboard. And if your motherboard supports dual channel, then either go with what you have now or another set of 2x512 RAM, don't get a single stick.
EVGA 680i SLi
E6400 @ 3.0 GHz
4 GB OCZ Platinum Rev. 2 EL @ 880
400GB + 250GB Seagate Barracuda SATA2
Antec P180B Case