First, I was having the following issue:

One day I reboot the computer. Board posts, fans spin, HDDs spin, etc just like every thing is working properly. Except the monitor displayed an empty black screen with the message "No PC signal"! I turned off the computer and cold started. Same issue. I cleared the CMOS jumper in the back, hit start, and voila... every thing works! Until the next reboot or cold boot , where the monitor is black and "No PC signal" I had to clear the CMOS jumper before every restart to get things working properly.

I've been doing this for two weeks before I got some tips. "Try changing the CMOS battery." OK. So I turn the computer off, do some cleaning, try a different battery, re-hook every thing up.... and.... no response on the power button at all. It doesn't even try to boot.

The board appears to be permanently stuck on CC post code. According to my manual, this is the invalid CMOS jumper setting code. Except the problem: both the CMOS jumper on the back of the computer, and the motherboard 1-2-3 pin jumper, is correctly set to the default mode. No combination/alignment of the 1-2-3 pin cap or the CMOS switch on the back removes the CC post code. Except I recall the board being stuck on CC post code and booting up before.

I never suspected a power supply issue, because while the motherboard was having stability issues with RAM, seemed to be stuck on CC post code, and had the monitor problem, the computer (once booted) would successfully idle for weeks at a time.

I'm super confused because nothing's really changed since the moment I unplugged my computer, popped out the battery, did some cleaning, and reset the motherboard jumper. Now pressing the power button doesn't accomplish anything... the board just sits there, lit up, with CC post code.