no power to motherboard

[danbeaver]

Step One (1): Buy a multimeter
Step Two (1): Google basic use of a multimeter
Step Three (3): check voltages a) Out of PSU, b) In at motherboard (FDD connector)
Step Four (4): Try another motherboard -- a stripped MB with voltages reaching it and no response needs evaluation and then repair by someone with more than a multimeter.

[danbeaver]

Not to be contrary, but that wiring harness is for an A4000D and I assumed you had an A1200.