PC turns on, then off, then on again

Hello to the best techie site on the net, I'm a long time reader and can usually just find the answers in thread, but I have kind of a strange issue. I just build a new machine (parts bellow) and on occasion when the machine is booting up it will turn on, then off, then on again. I am going to try the bellow, any other thoughts? Once the Computer starts running windows, all is good.

1) Remove all components from case and short the power switch pins to see if there is a short in the case/power switch.
2) I am trying to get another power supply to try with the board to see if this is a PSU issue.
3) I will try placing the PSU in an old machine to see if this is a PSU issue

i5 2500K CPU
ASUS P8P67 Pro Motherboard - 1053 Bios
G Skill ripjaw 4GP Ram
CoolMaster Hyper 212 CPU Cooler Plus
Corsair 650w PSU
Antec 300 Illusion case
WD 750GB Black HD
MSI Radeon 6850
Wind 7 x64