What could possibly cause my computer to power down at random times?

I have recently bought a new Power Supply and a new graphics card. My PC ran smoothly for a few months now but since a couple of days I'm having a strange problem. I am trying to isolate the problem to a specific piece of hardware (because if it's either the Power Supply or the Graphics card they are still under warranty).

The problem started when I was playing a game (diablo 3). My PC suddenly powered down. I was unable to turn it on again by pressing the power button. I unplugged the power cable for a few seconds and plugged it back in. This time the pc powered on but the indication light turned orange instead of white as it normally does. The fans were not spinning and I did not see anything on my screen.

After trying a couple of times I gave up. Two days later I tried again and this time the PC did boot up as usual. Everything looked okay until I tested if the problem was resolved by starting Diablo again. After about two minutes it powered down again as it did the first time.

If I don't run any games my PC does power down after about 3-5 hours.

Another fact that might be relevant: One time the PC did not shut down immediatly, instead first my graphics "powered down" but the music I was playing kept on playing. After about 20 seconds the pc powered down completely as usual.

What I also noticed is that when I boot instantly after a power down, the chance of another power down occuring is much higher.

Does anyone have an idea what could be causing this kind of behaviour or has a certain tool to diagnose the specific hardware parts?

Thanks

Specs:

Memory: 6GB
Processor: Intel i5
OS: Windows 7 64 bit

The PC is a Dell Studio XPS 8100 with a replaced PSU and Graphics card:
PSU: Corsair CX500 (500 watt)
Graphics card: AMD Radeon 6850

EDIT:

Something "new" happened this morning. The power light blinked orange and my fan was spinning in intervals of like 1 second.

geoffreydv

Posted 2012-10-03T20:35:35.663

Reputation: 121

2did you check temperatures? – poz2k4444 – 2012-10-03T20:37:35.773

Yes, they look normal. – geoffreydv – 2012-10-03T20:45:27.200

Have you tried unplugging and replugging everything? – Daniel R Hicks – 2012-10-03T21:24:24.270

1It could be that perhaps your power supply is malfunctioning and not putting out enough power to the hardware, or perhaps the graphics card is using up to much power, or a combination of both, do you perhaps have another computer you could put them in to test? – user88311 – 2012-10-03T22:01:47.620

Answers

It turned out to that one of the connectors of the PSU was broken. The connector got replaced and everything is working great again.

geoffreydv

Posted 2012-10-03T20:35:35.663

Reputation: 121

1i'm pretty sure the correct answer was given by @Ace Legend. You should award him the check. – Mikhail – 2012-12-02T11:42:51.960

So "If it is not overheating, then I would assume it has something to do with the Graphics card and OpenGL." would be the answer to a broken power supply connector? – geoffreydv – 2012-12-02T19:29:50.600

No. Keep the check where it is. My answer did not solve "your" question. But in case someone has similar issues and they stumble upon this page, they have my answer in case it applies to them. Glad you fixed your problem! – Josiah – 2012-12-02T20:23:32.230

It is very possible that this is because of a fan issue. Make sure your fans are running well and that your computer is not overheating. Overheating on a computer will cause it to shut off immediately so that it won't ruin the hardware. If you have a broken fan, the machine will overheat quickly while playing a high performing game such as Diablo 3. If it is not overheating, then I would assume it has something to do with the Graphics card and OpenGL.

Josiah

Posted 2012-10-03T20:35:35.663

Reputation: 1 674

1+1 This sounds a lot like a cooling issue. Grab a sensor probe utility (RealTemp, CoreTemp, SpeedFan, etc.) and monitor your temperatures. Anything over 80C is something to look at, 90-100C is a problem! – Darth Android – 2012-10-03T21:55:24.067

I can think of a few immediate causes involving the power supply. You got a lemon and the fan isn't working properly and overheats. Another possibility is that your PC is trying to pull more power than what your PSU can supply. How many watts is the new PSU?

Added: With this new revelation of an amber blinking power light, Dell says this:

If the power light is blinking amber – The computer is receiving electrical power, but an internal power problem might exist.
Ensure that the voltage selection switch is set to match the AC power at your location (if applicable).
Ensure that the processor power cable is securely connected to the system board (see page 73).

UtahJarhead

Posted 2012-10-03T20:35:35.663

Reputation: 1 755

It is 500W, which should be enough (I think) – geoffreydv – 2012-10-03T20:46:28.807

How many drives and video cards are you running in the PC? – UtahJarhead – 2012-10-03T20:47:54.263

There is 1 drive and 1 graphics card. I am pretty sure it can pull enough power because my pc ran smoothly for a few months without any problems after the new hardware. – geoffreydv – 2012-10-03T20:56:19.797

You have either a bad connection between the PSU and the motherboard, a PSU that's failed or a motherboard that's done. It is power related, though. – UtahJarhead – 2012-10-04T12:12:31.760

Read this: http://johnlamansky.com/tech/a-blinking-orange-power-light/

– UtahJarhead – 2012-10-04T12:21:44.247