m_neugebauer00 said:
I tested the power supply with a power supply tester and everything works when i test it
a "power supply tester"? I didn't realize such a device existed? do you mean you tested it with a multi-meter??
try shorting the power switch pins on the mobo wih a flathead screwdriver to see if you have a faulty power switch
Even though you "tested" it, if you have a spare PSU, try it out, if not, then...
1.) unplug everything from the mobo and clean it (blow out any dust, etc.)
2.) remove the CMOS battery and clear CMOS (if the board has a CMOS clear jumper, use it), wait at least a minute before reinstalling the battery
3.) then install 1 stick of RAM, a video card, and the boot hard drive -nothing else!
4.) now plug the PSU into the mobo, plug in AC power, and try to power on
if it boots, then reinstall 1 component at a time and reboot