Another new build that won't power up

[gb923]

Hello. I've tried everything I can think of to earn my junior system builder badge and need some help.

Here's what I'm trying to put together:
Intel Q6600
Gigabyte GA-P35-DS3L motherboard
2 gb OCZ dual channel ddr2 memory
Thermaltake Toughpower 700W power supply
crappy PCI-E video card since my 8800GT hasn't shipped yet.

Here's what's happening: On the first boot, and on a couple other tries after long waits between problems, the computer boots just fine. I can get into the bios and see the memory, fiddle with the date and time, and all looks good. The rest of the time, bad things happen. I push the power button, fans spin up, the intel fan on the processor stutters, then starts to life -- and everything dies. If I cycle the power switch on the power supply, it'll do it again and again.

I've taken everything out and reseated it. The 24 pin and 4 pin power connectors are both on.. the intel fan is seated on the board correctly and should be making good contact. Am I missing something? Any assistance would be appreciated!

Thanks!

 

[akhilles]

Could be an extra standoff or loose screw shorting out the mobo. Try it outside the case.

 

[gb923]

I tried it outside of the case.. same result!

When it's cold it's fine, when it warms up a bit it won't start up.

 

[gb923]

It was the PSU. I hooked up an old one and the system came right to life. Hopefully I can exchange the sucker for one that works.

Thanks to all the dead build threads for help figuring this out