Computer will not boot after switching case

[madkapper]

I have had the following system working perfectly for over a year now

core i7 950
asus p6x58de motherboard
18GB DDR3 ram - 3x2GB sticks and 3x4GB sticks
750w casecom PSU
evga gtx 460

Today i purchased a Bitfenix Colossus case and after removing the components from the old case and installing into the new case i turned the computer on. It stayed on for about 20 seconds and then shut off.
Now whenever i turn it on the cpu and psu fans twitch and then nothing.
I have been trying to fix it for about 3 hours and i have tried unplugging everything, tested the PSU with the paperclip trick and breadboarding the MB.

any help would be appreciated.
i can provide pictures/videos if needed

thanks

 

[C0rehound]

All your power cables are plugged up right? Main power harness, CPU power, etc? It's the simple things you always want to double check first.

 

[madkapper]

yeh i have the 24pin eatxpwr and 8pin eatx12v plugged in fine

 

[C0rehound]

How about the motherboard mounts, check for possible grounds/shorts. Also the connector back plate. Client of mine once had a tab off the back plate that was sticking into the USB plug grounding out the system and causing all kinds of problems.

 

[madkapper]

ill try re installing the MB now with all the stand offs and making sure the connectors arent touching anything.
But wouldn't the fact that it doesnt work even when i tried to get it working with the MB out of the case mean thats not the problem?

 

[C0rehound]

Probably but I'm just narrowing it down. I'd almost be willing to bet it's the PSU, but first things first. Do you have another PSU you could try?

 

[madkapper]

re installing the MB didnt work.
Ill try a different PSU tomorrow and get back to you

 

[madkapper]

i just plugged the eatxpower in without connecting the eatx12v and the cpu fan starts up..originally it just twitched..