So basically i bought a new case for my pc, it was a stock Emachines, i switched everything from the old case into the new one. it booted up fine then when i turned it off and tried it again i couldnt get a monitor signal to last more than a few seconds.. now ive been messing with it, i tried resseting the BIOS and now i dont get any monitor signal at all ive took it all out of the case and tried booting without it, same problem, ive also tried 2 different monitors... nothing is working, i get power but i cant see whats on the screen because there is no signal.
Sometime an errant pin can be grounding out on the motherboard. I would look carefully at screws and standoffs for the motherboard. Also try unplugging the reset switch (it might be bad). Quite a few little issues could be causing this strange behavior.