In general (with a hardware error) what we look for is either random errors - or no evidence of a problem in the Windows logs.
This is not 100% certain - but it does give us a direction to start looking in.
Your UEFI/BIOS dates from 2010. Please check at the manufacturer's website to see if there are any UEFI/BIOS updates available for your system. Also check the readme file to see if they apply to the problems that you are having. Please be advised that flashing the UEFI/BIOS is a very unforgiving process - and one mistake can physically damage your motherboard. If possible, use the "inside Windows" flash mechanism (if your OEM provides one) - that is much more forgiving than the traditional (floppy drive) flash method.
Only 89 Windows Updates installed. Most systems have 100 or more. Please visit Windows Update and get
ALL available updates (it may take several trips to get them all).
Don't worry about the specific number, it's just important that you have checked and installed any updates that were available (and didn't experience any errors).
Beyond that, there isn't much showing wrong that I can see. In most cases, this means it's most likely a hardware problem.
Please start with these free hardware diagnostics:
Hardware Diagnostics
Why do you suspect the PSU? IME most problems are solved by the owner, so that's why I ask.
FYI - the only sure test for a PSU issue is to replace the PSU with one that's known to be good (or a new one).
Don't do that yet - we'll work on some more diagnostics to help isolate the problem.
Should you start buying replacement parts, make sure that you get them from a retailer that'll let you return them for a refund if they're not needed.
Finally, this report will help us a bit more (it makes searching for patterns easier):
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 Administrative Events
- 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:
Windows Kernel event ID 41 error "The system has rebooted without cleanly shutting down first" in Windows 8.1, Windows 8, Windows Server 2012 R2, Windows Server 2012, Windows 7, or Windows Server 2008 R2
While waiting for a reply, please monitor your temps with this free utility:
HWMonitor CPUID - System & hardware benchmark, monitoring, reporting