Well good luck. Hope all is well now!
 
It makes me nervous when something goes wrong, then mysteriously fixes itself!  But it is Windows, and sometimes a reboot clears a minor glitch.  But those were some seriously strange symptoms.
 
It may be worth a deep dive into Windows Event Viewer, to see if you can locate a clue to as to what was happening, in case the problem reoccurs.
 
Here is some info about Event Viewer, but pay special note to the explanation at the top of the first article about why not to worry about most of the errors that you may see.  Even a PC that is running fine may generate plenty of error logs.
 
But if you are really having problems, this can be a useful tool to do a bit more sleuthing with.
 
http://www.howtogeek.com/123646/htg-explains-what-the-windows-event-viewer-is-and-how-you-can-use-it/
 
And  http://www.sevenforums.com/tutorials/226084-event-viewer-open-use-windows-7-a.html

Good evening,
 
just in case, you can run a memtest and as you
own several PC perhaps PSU could be in cause.
 
Random faults are often consequence of bad stick of ram or PSU. 

Hmmm   thanks   
So running the memtest can tell? I've never done anything like that. Is it a Windows 10 diagnostic or a 3rd party program?
Michael

Here's a few tips on checking RAM.  Windows has a built-in test, that is worth a first try, but the best is the free 3rd party MemTest86.
 
Windows method:
http://www.pcworld.com/article/3040544/hardware/do-you-have-bad-ram-heres-how-to-find-out.html
 
MemTest86:
http://www.pcworld.com/article/2048282/how-to-find-out-if-your-ram-is-defective.html
 
Diagnosing RAM problems:
http://www.online-tech-tips.com/computer-tips/check-for-bad-memory/

If the memory test finds an error, you will be left to sort out which memory stick is at fault.  Typically you should run first with all memory installed, then if that fails, remove all but one module.  Then test each module, one at a time until you hit the bad one.
 

Well, that seems clear. Thanks   32 Gb of G Skill can fail, too, I suppose.
We'll see what she wants to do next.
Thanks to all. It's all new to me, fortunately.
Michael

Or you could just swap all the memory between your PC and your wifes's PC.
 
If that moves the problem to your PC, at least she'll be happy! 

Now there's a solution that did not come to mind..... mine, anyway! LOL We had some ADATA but I think she sold it on eBAY, once we both got the G Skill.
It is a possible experiment, none the less.
Michael

Happy wife, happy life! 

Yes, indeed! LOL      Amongst my pals, that rings true and always gets enthusiastic confirmation!