Hi Dan,
As always, when this kind of problem occurs it is a problem to find out what exactly is causing the problem and, of course, you only have a limited time to RMA the board if it is the component causing the problem. I know this is frustrating especially as you have now gone and bought a new PSU (sorry about that) but, on the bright side, at least you now have one that will do the job.
What I would do, if faced with this problem is go right back to the beginning. I have checked and your choice of CPU is OK for the Motherboard, without a BIOS update so we need to be looking at why the thing won't start. The best way to begin this kind of troubleshooting is to put together the PC outside of the chassis. Get your motherboard and place it onto a non conductive material, I use the Motherboard box for this. Then add the CPU and cooler, 1 stick of RAM in the first slot and, if possible attach a PS2 Keyboard. Don't forget to connect your monitor to the appropriate connector on the Motherboard. Attach the 24 pin and 8 pin power connectors to the motherboard. If you do not have a set of test kit switches attach just the Power switch and reset cables from your case to the appropriate headers on the motherboard (manual page 28) and the speaker then try and start the PC. What happens?
