Computer instant reboots after installing new GPU (No errors)

[Cpt Porse]

Hello, Tom's Hardware community.

I recently started upgrading my desktop computer, and so far all components, besides the PSU is less then 1 month old.

My spec at the moment is as following:

OS - Microsoft Windows 7 Home Premium
CPU - Intel(R) Core(TM) i5-3450 @ 3.10GHz
w/ Arctic Cooling Freezer 7 Pro Rev.2
RAM - Kingston Hyper 8GB DDR3, 1600 MHz
MB - Gigabyte H77M-D3H, LGA1155 Socket
GPU - Gigabyte GTX 660 - Model N660OC-2GD
PSU - FH-POWER 600W (Can't Google it :S)

Yesterday i received my graphic card as the last component on my to-buy list. Up untill then i ran with no GPU on a newly formatted hard drive. But after installing my GPU, problems started happening:
Every time i boot up games like Diablo 3 and World Of Tanks with high settings on, after a certain amount of time (varies from 10-60 min, i dont really see any pattern) the machine just shuts down, and instantly reboot. No Error messages (besides the usual Do-you-want-to-start-in-safetymode option) and no Blue Screen. The only other games i have tried was Walking Dead Episode 4, which i completed in 1 go without shut downs.

What i have done so far:

- I have made sure all drivers are up to date, using Driver Detective
- I have monitored the GPU temp, and it never gets past 60 degrees Celsius. I have even had shut downs at 50 playing WoT.
- I have run 2 OCCT stress tests. One for GPU:3D errors for an hour, and a Power Supply test for an hour. None which gave any unusual results
- I have updated my BIOS to the latest version useing recommended programs and procedures from Gigabytes homepage.

I got a feeling the problem is my PSU, but as far as i can read, a 600W PSU should do the trick. My previous GPU was a GTX 460, which uses the same power in idle and under load as my new GTX 660.

Does anyone have any suggestions for more troubleshooting and solutions? I don't really want to just go and try to buy a new PSU, since i'm already stretching my budget.

Thank you in advance!

 

[Sunius]

Did you connect the 6-pin power connector from your power supply unit to your graphics card?

 

[Limerick]

Yeah did you make every signle connection from the gpu to psu?

 

[Cpt Porse]

The GPU is connected with a PCI-Express power cable similar to this one:
http://www.alibaba.com/product-gs/371995432/6_Pin_PCI_Express_to_Two.html

 

[Sunius]

You should connect it without the adapter - just directly from the power supply unit.

 

[Cpt Porse]

I'm positive i did that allready, but i got a shut down from that as well. I switched to the adapter since the wire colors (brown and yellow) made me unsure if it was right. I can switch back easily

 

[Sunius]

The card might be faulty. Do you have a good friend or neighbor in whose PC you could check whether it happens as well with that card?

 

[Cpt Porse]

I'll see if my neighbor will try out my card I'll post an update when i get around to it. Thx for the help!

 

[Sunius]

No problem .

 

[Cpt Porse]

After tinkering around with my Graphic card in other PCs without being able to pin-point any errors on it, i finally threw in the towel and ordered a new 750 W PSU, and i'm happy to say it fixed everything.
I have been playing under full load for +8 hours at a time, temperatures not exceeding 55 degrees C for a couple of days now, so i guess that was my problem.

So if anyone else is experiencing similar problems as i had, it might be your PSU

Now.. how do i close this thread and select best answer? I don't see any obvious buttons to click

 

[Mousemonkey]

Try it now.

 

[Cpt Porse]

Best answer selected by Cpt Porse.

 

[Cpt Porse]

TY Mousemonkey

 

[Mousemonkey]

NP.