GPU issue... or PSU?

Hello,
I recently just built a desktop everything went well it was my first build. i plugged in my GTX 560 SE to my system and in bios it says that the priority graphics are pci express, and when i switch to on bored i see a dramatic decrease in fps, but i cannot update the drivers for the gtx 560 se it says the card is not detected i have a 550 watt psu but it could be the issue,

the computer specs (if more info is required ill provide)
intel core i5 2500k
evga 560 se
Asrock H61M-DGS
550w dual fan switching power supply