I have been trying to trouble shoot the Windows 7 system which would not boot. I immediately checked the PS with a tool I have and also did the wire short test (black/green wire on connector) It showed to be good. I then re-seated the 2- 1gb ram modules..still nothing...It will power up the fans and sometimes give me a single beep and then it dies. I push the power switch...nothing. I unplugged the power and pushed in the switch for 1 minute and it does the same power on as I mentioned above. I then looked for bulging caps...none. I then installed a new PS with same results. I then removed the heat sink and processor and cleaned and re-installed new thermal compound...now, it powers up and off repeatedly every 2 to 3 seconds. Cmos batt is 3.15v
I forgot to mention when I installed the new 430 PS, it allowed me to go into bios to check some settings and then loaded the OS and I started running Malwarebytes scan. I came back to my office 2 hours later and it was dead again.