Ok, bought a Tagan EasyCon 530W a few weeks back, built up the PC and tried powering up, the only thing that happed was the LED's on the fans lit up for a millisecond and then nothing, tried this a couple of times after disconnecting from the plug waiting for a bit then trying again. Then the thought occured to me that it might be to do with either combined or split 12V rails, so I switched it to combined and hey presto, it works. I read the manual, didn't say anything, thought it might be something to do with loads but I only have

3700+ San Diego
Asus A8N-Sli
1 Optical Drive
2 x Akasa Amber Fans

I dont think its being stressed at all as it works fine when the 12V rails are combined.

Anybody have any idea what this could be or if something can/needs to be done about it.

Cheers for the help