There are a lot of threads about cpu problems but couldn't find anything to help. I've had this build for a couple of years and lately i've done some upgrading. Yesterday I bought a used gpu XFX5770 and it worked fine, did some gaming etc last night. Today my cpu arrived, installed it and then a problem came. Computer starts like normal but it stays in that state and nothing happens except it will restart after about 20 seconds and same happens. It doesn't beep like normally or anything, gpu and cpu cooler fans spin and lights come but no boot. Tried to reset cmos and try different combinations of ram, and also without gpu so i think it's not psu. Any ideas?
before i had Amd athlon x2 7750be
Amd phenom II x4 955be with thermaltake spinq vt
Altis A-550DX 550w