Okay I'm new but I have done my homework, have read close to 100 threads now before posting.
First off, here is my specs (yes I know it's old):
MSI K8N Diamond Plus
AMD Athlon 64 3700+ Socket 939
OCS Gold Edition PC4000 Dual Channel DDR(500mhz)
Silverstone 560Watt (but more importantly, 38Amps on 12v rail)
2each Geforce 7600GT in SLI
Okay, now as I said I have done much research and think I have a faulty mobo, not positive though. I need to pinpoint the problem and also figured out WHY this happened.
My computer, when pressing the power button, starts up for 1 second then shuts off. All fans spin, etc, but no beeps (presumable because its only on for 1 sec). After this I see that the LED on the back of my PSU is red, when normally it is either Green or Orange. I have found out red might indicate circuit protection has been initiated.
Okay, so maybe I have a short.
I pull out the components to do a bench/breadbord test. I start with the bare essentials. I swap out ram sticks, one at a time to see if they might be bad. I try another socket 939 processor. Still same problem, starts up for 1 sec then immediately shuts down.
I try jumping the pins for the power switch, thinking the switch might have been faulty, but it is not, same problem. I try jumping the 'green' wire and a ground on the 24 pin mobo connector, to test the PSU. It comes on and stays on until I disconnect these jumped pins. So it would appear the PSU might be okay (was not a load test, but still...)
Now I am down to possibly the mobo, I inspected with a flashlight and magnifying glass, no bad capacitors, no burnt components that I can tell.
Thinking my next step is to dive into PSU testing with my multimeter, but I will have to read up on that first.
Here is the kicker: When I disconnect the 8pin CPU connector (the one that plugs into the mobo to give the CPU its power), when that is DISCONNECTED, then the computer will power up and stay powered on. Once plugged back in, however, and tried to start it does the 1sec on then dies thing.
So, i guess there might be short circuit in the cpu/mobo/psu wiring somewhere, just not sure where.
Seriously guys, anyone have any ideas as to what could this be?