Motherboard (Gigabyte ga-k8ns-939) won't boot anymore and POSTS successfull even without ram and graphics card

tokli

Honorable
Jan 7, 2014
2
0
10,510
My PC does not boot anymore. The graphics card, the ram and the psu are fine (checked on another PC) and the cables are plugged correctly (ATX + 12V CPU Supply). I already did a CMOS-Clear and changed the battery. I also checked the "No POST", "system won't boot", and "no video output" checklist.
The weird thing is that my MB always beeps once when started, even if no ram or graphics card is plugged. The only problem i could think of right now is a broken CPU, which I can't test, because I don't have a running system with the socket. Are there other possible problems? Any ideas how to solve this issue? Or is my MB dead? Thanks in advance