M2-ATX power (sometimes) but no boot
I'm bench testing my setup:
Intel DG45FC with Celeron
Seagate 250GB 2.5" SATA (disconnected at the moment)
When plugged into the AC-DC PSU directly, the system will boot and go into the BIOS configuration (jumper set for this). Everything checks out OK.
Now, when I have the PSU connected to the M2 ATX (12v constant, 12v switched, gnd), the system will appear to power up most of the time... the mobo light will go on, the fans will run, but it won't boot. Other times the fans will spin for 2 seconds and then cut off.
There's a strange ticking noise coming from the motherboard speaker when being powered by the M2. The only thing I can think of is a ground leak or something. Any recommendations or thoughts?