Shuttle Power problem

[PUN]

I've had this shuttle for about 10months now.
When I booted today, it turned on (lights and fans) but immediately shuts off (like 1/2sec).

1. When ACPower is plugged in, I get lights on my mobo.
2. When the power button is pressed, it shuts down along with the lights on my mobo. When I unplug and plug back the power, i get my lights back on my mobo.
3. Sometimes when I press the power button and reset button held together, the lights on the mobo stays on, CPU fan spins, hear my HD, but DVD is not powered on with no display.

It's not my video nor memory. So it's down to bad CPU/PSU/Mobo
I know that even without a CPU, the lights on the mobo and fans stay on. So it narrows down to the PSU and Mobo.

I do not want to buy a PSU to find out that it's my mobo that is causing this problem.
Any help is appeciated.


UPDATE: with the 4pin power unplugged, mobo, fan everything else works except the DVD and CPU (obviously). Do you think it's my CPU?

 

[mpilchfamily]

No. The problem is the PSU. Replace it. Especially if the PSU came with the case.

 

[PUN]

Earlier tonight, I've tested:
1. CPU (works)
2. Video (works)
3. Memory (works)
4. PSU (works)
5. HD/DVDrw (works)
my mobo LED/fans and everything spins but it will immediately shut. My DVD does not power on (although everything else does). I think there is a short circuit somewhere, refusing to boot.

 

[IlllI]

i had a similar problem.. in my case it was b/c it was not being properly grounded or something. like a certain piece from the mobo was touching metal from the case. i don't know the exact terminology

 

[PUN]

Yes, it seems like something is shorting it. I rewired everything earlier today but I'll check again for any loose pieces or objects touching the mobo. I might have to RMA this thing.