Cyberpower PC Randomly Shuts Off

I am hoping someone can help me. I bought from walmart, a CyberpowerPC Desktop several months ago. Within the last two months or so, my computer has randomly shut down. No warning anything. It stays off, until I turn it back on it. Therefore unlike so many others from researching, my pc is not doing random restarts. Merely shutting down.

Thinking it was my PSU, I put in a different one, a Zalman, 850Watt PSU (Used, was given to me by a friend.) into my system. It still just powered down. No warning. I could be just checking my email, watching netflix or playing a game. No one thing causes it to power down over the other.

Upon checking around, I downloaded Speedfan, however, there are no tempature results, as shown in the screenshot included.

My PC Specs are as follows:
CyberpowerPC Gamer Ultra GUA-380 (According to Belarc, it says CyberPower Inc. MS-7641 4.0)
Windows 8 (x64) (build 9200)

Processor: 3.80 gigahertz AMD FX-4130 Quad-Core
192 kilobyte primary memory cache
4096 kilobyte secondary memory cache
4096 kilobyte tertiary memory cache
64-bit ready

Motherboard: Board: 760GM-P34(FX) (MS-7641) 4.0
Bus Clock: 200 megahertz
BIOS: American Megatrends Inc. V17.13 12/14/2012

Drives: 999.84 Gigabytes Usable Hard Drive Capacity
942.96 Gigabytes Hard Drive Free Space
HL-DT-ST DVDRAM GH24NS95 [Optical drive]
TOSHIBA DT01ACA100 [Hard drive] (1000.20 GB) -- drive 0, s/n 13MUHJGPS, rev MS2OA750, SMART Status: Healthy

Ram: Slot 'DIMM1' has 4096 MB (serial number 722F0000)
Slot 'DIMM2' has 4096 MB (serial number 742F0000)

Graphics Card NVIDIA GeForce GT 610

Is there any idea why my PC would just randomly shutdown? This has me concerned and any helpful advice would be greatly appreciated.

 

Overheating.
It could be a) thermal paste needed on heat sink b) if CPU has a fan that might not be attached properly or is working intermittently c) case fan might not work d) could be dirty inside and need cleaning.

 

I did have to clean the heatsink, it was filthy. Other fans seems cleaned, and properly plugged in. PC ran fine for about 3 hours, then went back down again. I have no idea how to tell which fan may not be working right. I ran SpeedFan again, and Fan1 is reading at 12RPM. While Fan2 is reading at 2961 RPM, and Fan3 is not reading at all. No temperatures shown again, save GPU at 53C and HDO is 33C. GPU before with speedfan did not have a flaming symbol next to it, but now does. Becoming frustrated.

 

HW monitor-

http://www.majorgeeks.com/mg/get/hwmonitor,1.html

Coretemp-

http://www.majorgeeks.com/files/details/core_temp.html

Sandra lite 'shareware'

http://www.majorgeeks.com/files/details/sisoftware_sandra_lite.html

Any of these will give you temperatures, many monitoring programs have trouble with certain sensors so try them all until you find one that works, Sandra has the most complete set of monitoring tools.

I'd like to see your temperatures also before taking shots in the dark.

 

I will download those, and see if any of them help. Will post results as soon as I get them.

 

I'd backup all your critical data then call the manufacturer tech support and have them troubleshoot it with you. This is assuming it's still under warranty. If your out of warranty.. here's a few things you may want to try.

I'm assuming all cables are plugged in firmly and nothing has or could be coming undone and the monitor is good? I'd want to rule out any form of malware. You can do this by starting the computer with something like Kaspersky Live Rescue Disk. Google it and download/burn the ISO. Start the computer with the disk in the drive and run a full through scan. Assuming the computer doesn't take a noise dive on cue and no infections are found I'd move on to the next possible culprit.. the PSU.

One of the most overlooked components in budget machines and in some off the shelf brands in general is the PSU. From what you've said I'd want to ensure it isn't the PSU, even though you said you tried another there's no way to know the other PSU is a known good part. You can test the PSU using a multimeter or by buying a PSU tester available on eBay, Amazon, Newegg etc they typically cost $10 or $15.

Rule out overheating as a possible cause, ensure fans are lint and dust free. Lint and dust act like an insulator on your heat sinks and add weight to fans. It is critical to keep your computer away from pets, off carpeted floors and if possible up on a desk. An annual dusting with compressed air inside is highly recommended preventative maintenance. Check the temperatures of the motherboard and the CPU as has been suggested via software. Keep in mind AMD CPU's do generally run a bit hotter than their Intel counterparts. You should also be able to check temperatures via the BIOS. If the CPU gets too hot it should throttle back to reduce heat output. If temperatures continue to rise it should shutdown to prevent damage to itself and the system.

Next I'd check.. be the motherboard and everything else. This part might be tricky if you don't have any spare parts to swap out. I'd start by disconnecting everything connected to the computer and start with just the HDD and 1 stick of RAM and run a benchmark see if it dies. If so try the other stick, swap out the video card (assuming your using an add in card) if possible and test again. Keep going like this until you find what it is or what it isn't.

Once you've confirmed what it isn't that leaves only what it is.. the motherboard/cpu itself. Experience has taught me typically if the board goes bad the CPU remains good 9 times out of 10 at least. If you tried everything else and nothing works. Swap out the motherboard. Unless you find the same or very similar board (e.g. same chipset) you'll most likely want to re-install Windows. You will have to reactivate windows in either case with MS when swapping out a major component such as the motherboard unless it's an identical part.

I hope this helps or provides some assistance. Good luck! Post back let us know what you find. That is assuming you don't have a warranty to fall back on.