Problem somewhere PSU perhaps???

Im having some problems with my rig just shutting off on me very randomly. I could be playing games, I could be on the net, or I could just be standing there looking at it. Its not restarting I have auto restart shut of...no BSOD just off. Sometimes I press the power button and it comes right back on, Sometimes it comes on as i'm pressing the button but as I release it it shuts right back off. When this happens i have to shut it off at the power supply and then turn it back on hit the power button and were back in business. So I think its a PSU issue. The PSU is a raidmax 630W. heres what its running....
asus crosshair mobo
2gig corsair xms2 pro DDR2 800 PC 6400...4-4-4-12 @2.1v
AMD X2 4600 overclocked to 2.8g
Twin BFG 7900GTX card in SLI
Raptor 10000 rpm sata drive


Its all wrapped up in a Coolermaster Stacker 832 case w/ 6 120mmFans
and a zalaman cooler on the CPU. CPU temps are in the sub 30's at idol and the GPU's run at 47 at idol. So I don't think heat is the issue. Please let me know if you agree with the PSU swap or if you think it may be something else. If you agree wtihthe PSU what are the really good brands you would suggest.....enermax...thermatake...coolermax ..I see corsair is even in the PSU game now. Thanks for the advice in advance i really need some input before i put another couple hundred into this thing....Money doesn't really matter but i would like to stay in the 200 dollar range ....TYVM for the help and input...

I couldn't imagine any other reason for this kind of behavior besides heat or the PSU. If you know someone with a beefy PSU that you could borrow and test, that would be great. If not, I would probably upgrade that PSU anyway. Raidmax isn't the best brand of PSUs, exspecially for a system like yours. I would probably go for a Silverstone, OCZ, or PCP&C if you can afford it. However, I'd wait for other people's opinions before shelling out for a new PSU.

Thanks for the input AF. I was wondering is it possible for a PSU to overheat? I noticed tonight that both times its died (so far) I was playing a game and after it happened i had to let it sit for a min before restarting or it does the flashy thing I mentioned be for. The only heat coming out is the PSU exhast ...all other exhast fans are cool. Im stationed overseas and have no way of testing it with another PSU right now (ill try to see what i can come up with) so if i notice any other details ill post right away. I hope everyone can help me come up with something were confident in...... Before i give new egg more money TYVM for any help

I thought of something else...I remmeber this happening with my the very first BFG card...the lovely 5700 OC. The PSU wasnt strong enough to support it so everytime i played a game and that GPU started to draw power BAM system down. Think this could be the same thing?

Alright right little more info for anyone who decides to comment. I punched my rigs info into a PSU calculator and found that Im right at the 630w mark and using a 630w PSU. So now im pretty certain that it the PSU bring down my system. Please HElp me Pick out a Good one I've been reading reviews and reviews and it looks like ill be spending at least 200 250 if not more so i really want to be sure i get a good product........

what up with this futron ??? i think thats it company and this booster PSU thing they make. and is enermax a good company TYVM