New build system shuts down during gaming

[coltus]

Just built a new computer on friday and have been getting system shut downs while gaming.
System is stable during web browsing and dvd watching.
CPU seems stable with Prime95, i've also checked memory with memtest86.

Games tested
The Witcher 1 - crashes during intro.
Mass Effect 2 - crashes after about a min of playing.
Battlefield Vietnam (old one) - display goes off and system locks up after about 10min.
Battlefield 2 - crashes after about a min of playing.
Crysis - this ones weird after about 10min the display goes black and
i have to close crysis with task manager. But the systems still on.

Also it doesn't seem to matter what settings i have in game be it all
low or all high.

System specs are

CPU i5 2500k @3.3GHz
Memory Corsair xms3 4Gb
GPU Gigabyte GTX 480 soc


PSU OcUK Battle 750W
+3.3V/24A
+5V/26A
209W Peak maximum

+12v1/24A
+12v2/24A

-12V/0.5A
-5Vsb/3A

Win7 Ultimate 64bit Clean install
Latest drivers

When the gpu is at stock speeds the computer will switch off like the plugs been pulled.
Using Oc Guru temp idles around 40C, the reading is also similar using gpu-z.
I've tried using occt to stress the card and it shuts off like when gaming.
However if i under clock the card to gpu 680MHz/mem 800MHz then the test will run.
As soon as the test starts i can then put the speeds back to stock levels gpu 820/mem 950.
Temps are stable around 84C with fans 100%.

I'm thinking that the psu can't take the initial power draw.
However when under clocking i'm able to play for about 15min to 1/2 hour before system shutdown.

All thoughts are welcome.

Edit forgot Motherboard: MSI P67A-GD65 Intel P67

 

[coltus]

The psu is a brand called Power Cool in case anyone was wondering.

@ olivier the only combined wattage is for the +3.3v and +5v which is 209W peak maximum.

@ -=Vect0r=- Using furmark 1.9.0 i can run Burn-in test for 10 min no probs. Total power for system including monitor was 470W
I can run Benchmark (no preset) Score was 4161 69fps. Total power was 550 peak of 570.
Benchmark 720 crashes system.

Using occt the system will crash unless i under clock until it has started then put it back to stock.

 

[coltus]

I just switched the power monitor so it was only reading the pc.
Furmark 720 was 520W at peak. So it looks like a new psu is in order.

I'm looking at
Corsair Enthusiast Series TX 850W V2
and
Antec TruePower New Modular 750W

Don't know if i can return the psu as i ruined one of the modular cables.
Still i hope the new psu fixes the problem as i've got the Witcher 2 waiting to be played.
And thanks for the help.

 

[coltus]

I went with the Corsair TX850 V2 which should come tomorrow.
I will update tomorrow once i've tried it.

Thanks for the help everyone.

 

[coltus]

Well there will be no eating of hat. The corsair tx850 works like a charm, power draw for the system is actually lower than the other psu.

At stock speeds 820/950
Furmark gave a score of 2073 34fps @ 1080
Heaven give a score of 1368 54.3fps @1600x1200
And occt 3.1.0 spews out errors and the the display driver stops.

Under clocking to 800/900 seems to be stable for at least 5 min in occt.
I'll it try longer later.

Anyway thanks again everyone.