Custom PC power cycles on/off, on/off then BSOD

[danigurl]

Have a custom built pc from 2009. Recently it has begun to power off spontaneously. Most of the time when it does this it tries to power back on but only runs for 1-3 seconds before powering off again. Sometimes it does it 3-4 times or more and comes back on, sometimes it stays powered off and sometimes it goes BSOD and may or may not generate a log into the minidump folder. I have also noticed that sometimes if I unplug it from the wall totally, then plug it back in it starts up immediately without me pressing the power button.

Here is what I have already done:
tested with different memory, with optical unplugged, with hard drive unplugged and booted from optical to an ubuntu session, with aftermarket video card removed, with front lcd panel unplugged, with all original components unplugged and spare memory in place leaving it in the BIOS setup screen. Checked the standoffs to make sure nothing is touching the case, added cardboard washers where I noticed there were none placed when the thing was built, flashed the BIOS, reset the CMOS, replaced the CMOS battery because, hey, why not since it's five years old and I was in there anyway, inspected the motherboard for any obvious signs of damage like burn or scorch marks, scratches, corroded, bulging or leaning caps, ran video stress tests, cpu stress tests, and did a clean install of windows.

I am about to tear my hair out with this thing, but I can't afford to junk it and buy/build a new one.

Any ideas anyone? I'll post the dump log and system specs too so you'll see what I do.

motherboard DH55TC running Intel i3 540, 4GB Crucial gaming memory, 2GB per slot, seagate barracuda 1tb hard drive (7200rpm), NVidia GTX 670, Corsair GS600 power supply, and sony cd/dvd rw combo drive. Windows 7 professional 32 bit.

==================================================
Dump File : 061714-63008-01.dmp
Crash Time : 6/17/2014 1:35:55 PM
Bug Check String : KERNEL_MODE_EXCEPTION_NOT_HANDLED
Bug Check Code : 0x1000008e
Parameter 1 : 0xc0000005
Parameter 2 : 0xd4863d47
Parameter 3 : 0xd9b42aec
Parameter 4 : 0x00000000
Caused By Driver : win32k.sys
Caused By Address : win32k.sys+c3d47
File Description : Multi-User Win32 Driver
Product Name : Microsoft® Windows® Operating System
Company : Microsoft Corporation
File Version : 6.1.7600.16385 (win7_rtm.090713-1255)
Processor : 32-bit
Crash Address : win32k.sys+c3d47
Stack Address 1 : win32k.sys+6cb36
Stack Address 2 : win32k.sys+6c53c
Stack Address 3 : win32k.sys+cbd6e
Computer Name :
Full Path : C:\Windows\Minidump\061714-63008-01.dmp
Processors Count : 4
Major Version : 15
Minor Version : 7601
Dump File Size : 163,592
Dump File Time : 6/17/2014 2:27:08 PM
==================================================

 

[notherdude]

Power supply. Try another one.

 

[danigurl]

Power supply. Try another one.

I thought about it possibly being the power supply, but I didn't have a different one to test with, or a multimeter or PSU tester, but I did download HWMonitor and it's sensing values in normal range. It's not powering off under load, it actually happens more frequently when it is under light use, just web surfing, office applications and such.

Will you tell me your reasoning behind thinking it's the power supply?

 

[notherdude]

Good idea not to leap to that conclusion just yet since you would have to buy another PSU but it did seem like the next logical candidate for testing. My reasoning is that you already tested so much else. The fact that it won't power back on after the shutdown (3-4 times)suggests something motherboard or power related and not OS related. (note: some motherboards will restart themselves twice after a hard shutdown, that is normal, but not 3-4.) That leaves psu, mobo, ram, or video.
You tried on-board video right? Same result? So that leaves RAM, MOBO, PSU. You tried different RAM, right? So now down to MOBO or PSU. It could be either but PSU is much easier to replace, hence my suggestion.

And yes I did forget the CPU but that is because CPU failure is extremely rare.

 

[danigurl]

I did test ram and, and tried onboard video with the same problems. I did a closer inspection of the board and found a couple caps that are leaning a bit but I think that they might have been bumped by the builder when he installed that massive video card. The vents all look totally normal on them and I tapped them with a chopstick (the most amazing probe ever IMHO) they weren't at all loose and as much as I could see the bottom didn't seem bulged out. I'm probably just going to give in and buy a PSU. At least if I buy one from Best Buy I can use it to test with and if it seems to be the fix I can either keep it or return it and order a less expensive one online. Yay for 14 day return policies.

 

[notherdude]

I did test ram and, and tried onboard video with the same problems. I did a closer inspection of the board and found a couple caps that are leaning a bit but I think that they might have been bumped by the builder when he installed that massive video card. The vents all look totally normal on them and I tapped them with a chopstick (the most amazing probe ever IMHO) they weren't at all loose and as much as I could see the bottom didn't seem bulged out. I'm probably just going to give in and buy a PSU. At least if I buy one from Best Buy I can use it to test with and if it seems to be the fix I can either keep it or return it and order a less expensive one online. Yay for 14 day return policies.

Exactly, the ability to return a PSU after testing with it is a good argument for next trying a PSU. Let us know and I hope it works!