Pc shuts dow for no reason

Hello my computer shuts down for no apparent reason their is no warning or error screen.I’m very satisfied with my pc i have it for month now and i’ve had no problem since yesterday while i was playing League of Legends. At start i thought that the problem was in the OS im with win 7 64x ltimate. When i reistalled my OS the problem still existed.
i noticed that this happens while playing games.
So please help me here is some info
Cpu- I5-2300 2.80Ghz
Ram : kingston hyperX 2x4gb
Mobo assus sabertooth p67 b3 rev
video asus gtx 550 ti
psu Huntkey green power 550W

IF that video card draws a LOT of power and you have a bunch of other goodies like many hard drives running and burners maybe once a game starts and the power draw ramps up for 3d games the power supply shuts down to protect the system from a short or voltage drop.
I have a fully loaded Hex core amd with a new to me 4870x2 and lots of drives and burners installed.
It was perfectly fine till I decided to run a game I haven’t played in a while on my new setup. It shut down just as the game started to boot into the actual game and continued to do it every time I tried to run it.
I had a real nice Nspire Xtreme power 750 with 4 18 amp 12 volt rails and over current and voltage protection. As soon as the card ramped up it would draw over 400 watts and maybe way over 25 amps on one of the rails and the PSU would instantly shut itself off to protect itself and the machine.
I had to turn the second core off and slow the clock way down to even allow the game to run.
Finally I found a good price on a 850 ThermalTake Black Widow PSU that has up to 69 amps on it’s massive single 12 volt rail, now everything runs great, even my games and not one shutdown since.
Just because your PSU claims it can do 550 doesn’t mean it REALLY can and with everything else in your box your probably just running outa juice and it shuts down. Barrow a known good quality bigger PSU and see if your issues go away. I’m sure others will jump in with what kind of juice that card needs and recommendations for good ones plus other ideas that may help you.

I agree that it is most likely an underpowered PSU. The only other thing that would cause a shutdown under those circumstances would be overheating.

  • System
  • Provider
    [ Name] Microsoft-Windows-Kernel-Power
    [ Guid] {331C3B3A-2005-44C2-AC5E-77220C37D6B4}
    EventID 41
    Version 2
    Level 1
    Task 63
    Opcode 0
    Keywords 0x8000000000000002
  • TimeCreated
    [ SystemTime] 2011-09-12T14:11:46.268813700Z
    EventRecordID 4643
  • Execution
    [ ProcessID] 4
    [ ThreadID] 8
    Channel System
    Computer jonkaminator-PC
  • Security
    [ UserID] S-1-5-18
  • EventData
    BugcheckCode 0
    BugcheckParameter1 0x0
    BugcheckParameter2 0x0
    BugcheckParameter3 0x0
    BugcheckParameter4 0x0
    SleepInProgress false

So the problem was this

check you´re bios power options and set it to POS S1 only these may help.

Okay, while you CPU uses very little power and the GPU is also light on power, it should work. BUT looking up a review of that PSU and at first it looked good, till I saw the tests… Its a pretty crappy PSU. At best it can put out 400W before things go down hill. Even while gaming you PC shouldn’t draw anywhere near 400W I would suspect that it is whats giving you the trouble. If you can return it.

One other possibility is that you may have forgotten to plug in the power cable that goes to the video card, that cable is required and not optional.

Quality PSU brands are Seasonic, Corsair, Antec, Enermax, FSP group and some others.

Link to review Review