I know how you feel, I had this problem also a while ago, it kept me bussy for like 4 months to find on my own the problem. Even proffesional pc bisness shops didn’t find the problem. Anyways if you talk about what I have encounterd.
Ok here it comes, beware the amount of text, but I think worth a read.
It began with that my computer suddenly rebooted while playing a game, doing some painting or else. I turned on my computer, I saw the computer being bussy on the leds, but it didn’t made a zoom sounds like when the HD starts to run and loads windows.
Anyways I had to reset the computer, even resetting didn’t worked, I ahd to push the big button and reboot it that way. Sometimes like 5 or 10 times before it came back in windows.
Afther 1 week I was sick of this and a lot of people had taken a lok at my pc and didn’t find anything. Afther this it kept showing blue screens afther like 4 hours to be turned on. Sumple memory leak blue screens or the famous x020359748975864 error blue screens.
A lot of people told me it could be the Ram memory cards that could be of poor quality and give up life, videocard that was broken, powersupply that couldn’t give enough power of was broken, fans that didn’t gave enough cooling, HD failures and a lot more. But google found something I didn’t know off.
I searched for broken or old cilinder stuff things on you Motherboard. Those things can get fatter afther time andlook like they can explode. THis causes instable motherboard which causes a lot of problems, like blue screens and such.
Anyways I screwed open my systembox and saw indeed that those things where, well close to exploding. I replaced my mobo with another and fixed was the problem.
Before I actually found out about that, I reinstalled windows like 8 times, installed different linux things on it, did use some system checkers that run like 12 hours to find pc failures, and a lot more. Actually the program that checked my complete system found something about a memory test problem but afther all it was the instability of the energy being managed on my mobo caused by those cilinder things, darn things
Anyways those where the problem. I would suggest to try out replacing things piece my piece and check the pc if something changes. I would start with your memory and mobo. simply just find a friend who wants to give ti for a few hours to you.
Ooh btw, the problem about those cilinder things, is was a well known problem on the k7 something ASUS motherboards. I have seen horror like photo’s of those things being exploded, yes no joke. Complete mobo’s burned by the pasta in those cilinder things, and then it’s over. I also was able to call the company and ask some new clinder things to replace by myself, I got those for free.