Yesterday I finished building my first system (Gigabyte GA-Z68AP-D3, Intel Core i5 3550K 3.4 GHz, Corsair XMS3 2x4GB, Gigabyte GTX 650 ti 2GB). Once I power it on, all the fans are working, everything seems fine however when I see the BIOS screen keyboard (USB) won't work and the system restarts. This keeps happening over and over again until I force a shut down with the power button.
I took everything out, reassembled the pc, tried booting with minimum components (CPU, heatsink and ram) and the same thing keeps happening, restart at BIOS screen. I also took out the MoBo battery for an hour, installed again but nothing.
I suspect it's the motherboard but I'm a total noob.
Any ideas or recommendations would be more than welcome!