How's this for weird from Antec.
Previously I had problems with an HE550W, Gigabyte GA-7V400AM and a Zalman VF700Cu VGA Cooler. System would not POST on silent (5V) for cooler fan. Finally got a reply from Antec to say that my motherboard probably required a -5V rail and as the Neo does not have one it would cause problems.
So I did my research and decided to go with an ABIT AN7 which by the manual requires an 'ATX12V power supply with 300W,20A +5VDC, and 720mA +5VSB capacity at least'.
Plug in my PSU to new board and system POSTS then starts booting to only crash a few seconds later. A safe mode start revealed that the last known device it was loading was 'mup.sys'. Do a google search on this and open up another can of worms!
This is the weird part. Plugged the Neo HE back into old system and total failure. System was exactly as prior to removal. Booted once, then reset after XP loading. Failed to restart. Pwr off restart just a click most of the time but sometimes a tease with a few seconds of whirring before shutdown. Stripped system back to bare essentials. Same problem.
Plugged my old 300W mini PSU (now my old faithful) in and system works fine. Even with sytem components replaced.
On to Antec now, see what they have to say about this one.