Machine powers down randomly

I first encountered this problem when playing Magic The Gathering on Steam and the issue seemed to stay unique to STEAM however, I have re-installed windows and now face the issue of my desktop powering down at random intervals without even having steam installed.

I am running windows memory diagnostics right now and will also test the CPU, HDD & GFX and report back when I am done with them all.

I'm 90% sure my PC is NOT overheating, I have faced this problem before on a different desktop and my desktop feels no-where near as hot as the last one did when it was over-heating.

It is a custom built desktop with AMD quad core CPU and 16 GB RAM and a 1 TB HDD with on-board nvidea graphics and also on-board audio, can post exact specs later if required.

Is there anything else besides what I'm testing that might cause this issue?

Thank you for your kindness in advance.

- One Frustrated PC-USER

o.k so almost 24 hours later all the results are in :

Unfortunately, I don't have the time today to do a heavy analysis, but try disconnecting both your front panel power-on switch, and the reset button switch. First test the Power-on switch: trace the cable from where it plugs in to the mainboard. You can use your manual that came with the computer to ID it, and it should be labeled on the mobo also, usually something like "pwr", or "pwr sw" or somesuch. Pull it off, exposing the contacts. Take a flat-bladed screwdriver and cross the two exposed contacts. The computer will power up normally. Let it run for two days or more and stress the heck out of it with a game of your choice. If your shut downs stop you found your problem....bad power switch.

 Do the Power-on switch first.

You can test the reset switch by just pulling off the connection cable and then run the computer normally. I have had cases where both of these failed and it is always the last thing I think of. It gets me every time.

Edited by ranchhand_, 24 July 2016 - 08:23 AM.

Overheating doesn't have to be noticeable to you outside of the case.  I once had an overheating video card (the temp sensor was defective also).  and I didn't notice it until I burned myself on the video card :0(

If you had problems in Ubuntu and in Windows - then it's OS independent (and this makes it more likely to be a hardware issue).

Just a thought, what happens when you gently move the case/gently move the exterior cables (and/all of them)?

Had this problem with an iMac at work the other day - another tech hadn't securely plugged in the power cable, so moving it would shut it off

Let's try looking at these 2 sets of reports:

1)  Please run this report collecting tool (even though you may not be experiencing BSOD's) so that we can provide a complete analysis: (from the pinned topic at the top of the forum)   http://www.bleepingcomputer.com/forums/t/576314/blue-screen-of-death-bsod-posting-instructions-windows-10-81-8-7-vista/
FYI - I don't often use the Perfmon report, so if it doesn't work please just let me know.

2)  Please do the following:
- open Event Viewer (run eventvwr.msc from the "Run" dialog)
- expand the Custom Views category (left click on the > next to the words "Custom Views")
- right click on the "Administrative Events" heading
- select "Save all Events in Custom View as..."
- save the file as Admin.evtx
- zip up the file (right click on it, select "Send to", select "Compressed (zipped) folder")
- upload it with your next post (if it's too big, then upload it to a free file-hosting service and post a link here).

FYI - If we're looking for Event ID 41 errors (unexplained shutdowns), there's more info on that here:  http://support.microsoft.com/kb/2028504

While waiting for a reply, please monitor your temps with this free utility:  http://www.cpuid.com/softwares/hwmonitor.html