Okay that you have problems while in BIOS suggest the video card or cable is bad. Have you tried swapping cables? Moved the video card? Did you check there is no dust / overheating? Otherewise I would ask your friend to bring his card and PSU, and test it in your computer. IF YOu get the same result then it is the 'crappy mobo' I would suspect. If as you test things (swap GPU first, no problem?, swap PSU, no problem?, swap GPu back with friend PSU, no problem? ) you should get down to what repeatedly causes the same issue. Now if you had problems during ALL this testing most likely either video cable or mobo at that point.