When I turn on the power the MOBO leds all come on, the fans all spin up, the optical drive begins to star and the hard drive begins to spin up but after 1-2 seconds it all shuts down. If I wait, touching nothing it starts up again. It continues to go through this loop until I turn off the main power at which time it will attempt to go through the cycle again for a split second before finally turning off (must be some residual power in the system).
I've stripped everything out and have tested the PSU by shorting the green wire to a black. It powers up and stays on.
And then one at time I've connected each of the following to the PSU, disconnecting before trying the next;
I've connected the optical drive and that comes on, opens and shuts ok.
I've connected the hard drive and that spins up ok.
I've connected the GPU and that starts up ok.
Then I reseated the CPU and fan, new thermal paste and all. I connected the 24 pin MOBO cable and the 4 pin ATX to the MOBO and switched on. It goes through the same loop.
I had no RAM inserted during that test so I tried it with the RAM, singly and the pairs in all combination, in all the slots. It made no difference.
To me it seems obvious that it must be either the MOBO or CPU but what do I know. I have no experience at this and I've never assembled my own computer.
What does everyone else think and is there anyway to test these things.
I don't have another system I can try either in and though under warranty it's been so expensive I have no money at the moment to go through the returns process.
Does anyone know any way to narrow it down and could I remove the cpu but keep the fan connected so I've only got the MOBO, 4 pin ATX and 24 pin MOBO connected? Or would this damage the MOBO in some way?
Disconnect anything USB, except, if applicable, kbd & rodent;
hold power switch depressed until MOBO finally shuts off completely;
power down at PSU switch, or, if no PSU switch, pull the plug;
while 'unpowered', momentarily short the CMOS_RST pins with a jumper, or a steady hand and a small, flat screwdriver blade;
remove all but one DIMM, in slot DDR3_1, second from CPU;
power back up - if able, enter BIOS;
do a "Load Optimized Defaults" from first BIOS menu;
<F10> to save, exit, and reboot;
power back down, and add remaining DIMMs...
If this procedure doesn't work, you're at the spot where you really need a case speaker - it's the only diagnostic info available at that point: http://store.cwc-group.com/casp.html
Oh - and, pulling the CPU won't hurt anything - but won't show you anything either - everything the MOBO can do at all is dependent on the CPU's fuctioning; if we sawed open your head, and removed your brain, pretty much nothing that's left would function at all
I'll have a look at that tomorrow. Bit late at the moment to be getting everything out again. Just noticed another post on this forum that says with the same MOBO it was his ram and have been told that a MOBO with no ram attached would give the same symptoms as with broken/not recognized ram. You learn something new . . . as they say. Will have a look at the voltage tomorrow and get another 1gb of ram to test in the MOBO. Will let you know the result. Thanks for your help.
Might also consider something simple but often overlooked....a 2 dollar front case on/off button. I had an issue like this where it would attempt to start, then shut off, rinse and repeat. The on/off front case power button was going bad, replacement fixed my issue. hARD to find. I found the power switch at someplace called axiontech.com
It certainly seems that way from all the other forums I've read. It's on its way back to the company I purchased it off. They've asked me to return the psu, cpu and ram with it. As long as they can't start it, it wont cost me anything. Just waiting to see what they say.