I just got a new pc with gigabyte gtx 760 windforce + asrock 980de3/u3s3 + amd fx 8350, its already set up, but when I power on, I get no video!! the monitor's led keep flashing as if there's no vga plugged... but when I change it to my old vga (8800gs) I get video fine.

I tried to upgrade the mboard's BIOS (from 1.10 to 1.30, latest) and still no success.. I'm really frustrated about that..
This vga is brand new and also is my psu ( corsair cx750)...

Do you have any clue ?? This motherboard has any known issue with this vga?? I couldnt find anything related to this...

any help will be appreciated
thanks