Computer restarts after entering 3D

[binary]

Hello,
I'm having some trouble with my new rig. The problem is everytime I try to play a game the whole system restarts. I thought it could be the PSU not being a high enough wattage but I used a few wattage calculators online and got results within my current PSU wattage. I have updated my bios, gfx drivers and direct x and still have the same problem.
My system is:
core i7 920 @ default speed
asus rampage II extreme
asus rog gtx 285 @ default speeds x 1
1tb western digital sata hard drive
samsung IDE dvd rom drive
750w lian li silent pro
corsair h50 liquid cooling

I have 3 led fans 2x 140mm, 1 x 120mm

other info:
Im using steam to launch games
on windows 7 profesional
ran prime 95 to test cpu and was fine
I think I heard a whizzing noise from the gfx card but could't pin point the exact location so might not have been it.
The gfx card is brand new so I havent had it run any 3D applications

I'm unsure on how I can debug the problem so any suggestions are welcome.
thanks in advance Binary

 

[mo' power]

Those online calculators are useless. I could see a system crashing when starting to play games but not restarting. If your pc is working fine while doing day to day tasks, my guess is the psu may be faulty. If you can find and swap a spare psu from a friend or family member's pc, I would recommend trying that first.

 

[crazyhorsejohnny]

No matter what kind of problem I come across I always test the RAM using memtest. I suggest you do the same and if it passes then try swapping your PS.

 

[binary]

I found someone else who had the same problem on the asus support website and they had a 1000w PSU, which leads me to believe it's a broken card. I've submitted a support ticket to my supplier and hopefully it will be dealt with soon.

Thanks for your input guys.

 

[mike.mgs4]

I found someone else who had the same problem on the asus support website and they had a 1000w PSU, which leads me to believe it's a broken card. I've submitted a support ticket to my supplier and hopefully it will be dealt with soon.

Thanks for your input guys.

Did you try running FurMark. Do a stability test and see if it runs.