PC randomly shuts off and randomly boots up after (sometimes).

[ExpendableG4M3R]

Hi there,

I am here in bad need of help to figure out what is going on with my pc of late.
A quick run down of the problem. When the PC is on it will depending on how long its been on will randomy just shut off. When it shuts off, it "sometimes" reboots but most often it "tries" to reboot but fails and then stays off. After this failed try to reboot if I press the power button on the case and mobo, nothing.
Now if I turn OFF the PSU leave it for a few minutes and come back turn the PSU switch on and press the power button the system comes to life for a second or two then dies and will no respond to the power buttons until I turn off the PSU again.

I have gotten it up and running from this state by leaving it off and unplugged for a couple of hours. When I say the PC comes to life for a second or two, I mean the case fans. If I get it booted up the BIOS is reset to default for some reason. Also if it makes it to windows, the notification area icons also gets reset... very very odd.

I have a short video of the problem, sorry for the darkness, I finally decided to video it and it was 11pm.

My first thought... PSU dying or Mobo. I dont have extra's so I cant test them.
Forgot to mention, ive checked for heat problems but none of my temps are high, they are all normal and its a Antec 1200 with tons of air movement. I keep my PC clean but this problem I just cant solve.
Event Viewer shows nothing expect for unexpected shutdown. My event viewer is clean from any errors also. I do not get any BSOD and this is on a fresh Win7 install from late Jan. Its been doing this thing now for a couple of months. I am 99.9% positive it is not a software problem.

https://plus.google.com/102949446272810497301/about/edit#102949446272810497301/videos

 

[ExpendableG4M3R]

Anyone have any suggestions at all?

I got the system up today and its running like as if nothing happened.

 

[Carbon6]

I would suggest seeing if you can try a friends PSU.
When the pc is up and running, can you drive it hard with a cpu and gpu benchmark software at the same time to see if you can get it to shut off under heavy load?

 

[ExpendableG4M3R]

Its done it with a light load just being on the net and is done it under a heavy load playing games like SWTOR with background music playing from WMP.

I think that the longer the pc is on without a restart or a shutdown the higher the chances it happens. Yesterday I had the PC on for roughly 8 hours straight and it died. But all of last week I never had the pc on for longer then 3-4 at a time without a reset or shutdown and it never died.

Why would my BIOS and clock always reset to default though when it shuts off hard like that?

 

[Carbon6]

The bios not holding data is usually a flat battery on the motherboard.
When you say "Also if it makes it to windows, the notification area icons also gets reset.." do you mean just the clock is reset?

If thats whats going on... BIOS not holding settings, and system clock doing the same, then a battery is usually called for.
How to replace the CMOS battery.

 

[razy60]

how old is the mobo? we had a similar problem with one of our PC's and it turned out to be the MOBO battery.
As for resetting the bios that's what normally happens when the battery goes.

 

[ExpendableG4M3R]

the mobo is about 3 yrs old. the battery could be flat but why would it only do it AFTER the PC randomly does a hard shutdown?

Its a complicated situation on what happens I guess and its hard to explain it clearly. The PC runs and boots up normally. Its when this randomly hard shut down that its a pain to get up and running again. When it does, the BIOS and clock is all reset to default.

Trying to figure out the cause of this random hard shut down has become very taxing and at this point im about to just pack this PC in and just get the new ipad and eliminate so many problems.

 

[livinloud01]

sorry to revive an old thread but i'm having this exact same problem. I changed the battery when the problem started. I have also changed the psu and ram since then. The mobo is a Gigabyte H55N-USB3 with an i7 cpu.

any ideas on what i should do? other than replacing the mobo.

 

[ExpendableG4M3R]

An old thread indeed but it turned out my motherboard was dying, then it just died. Replaced motherboard and everything was fine.