Posted 27 April 2012 - 04:57 AM
I've taken the components out of a working tower to make a testing rig and they are no longer booting. While they were in the case they would respond to the Power Switch, POST and allow me into the Bios ok. Now that they're out (on an insulated mat) they are powering up when I connect the power lead, PSU & CPU fans start up, there's a little click from the motherboard, and it shuts down. The power button then does nothing.
This is the setup:
Asus A7V600-X Motherboard,
AMD Athlon XP 2800+ processor + FHS
Powertronics 400W PSU (20 pin)
256MB 333MHz DDR RAM
Nvidia MX4000 128MB AGP graphics card (I think!)
Power button plugged in, or shorting the connection with a screwdriver - doesn't make a difference
I've removed all the components one by one to isolate the problem, and it's still failing the POST. I've reset the CMOS using the jumper as described on Asus' website's troubleshooting for this model mobo. I can only think there's an out-of-case failsafe built in, or something glaringly obvious that I'm missing.
Any advice appreciated