Did a clean install and its still there. Must be a hardware issue then all of a sudden? What could piece could cause this?
Hey
I'm really bummed out to hear that didn't work out for you. Since DISM didn't work out for you AND you did a clean install, as in reformat the drive and reinstall from an official windows copy and it's STILL causing you issues, then it does indeed point to a hardware issue rather than a virus or a quite rare but normal windows corruption.
We can somewhat safely rule out your graphics card because even if it were bugging up every now and then, it's not writing to your windows system files (where sfc checks), where you continue to find corrupt files. That's an important piece of information, especially considering you're running a fresh OS install.
While I don't know what hard drives you're using, It's also unlike to be the cause based on the fact that the freeze happens even while nothing is happening that would tax the drive. However, when running into weird issues it's never a bad idea to check the SMART status if possible, but still, I personally don't think that's the problem.
This leaves us with, in my opinion, four likely possibilities. You could have a bad CPU, one or more bad RAM modules (a bad or failing DIMM slot can deceive you in this regard!!) a bad power supply or possibly the motherboard itself, which is unlikely due to the fact that the computer is "working", but at a slower pace. I think some people would suggest a BIOS update but considering the problem seemed to come out of nowhere I do not think that would help you.
So, what now?
I would suggest trying some programs that test/stress the hardware components in question. The first program that comes to mind would be Prime95, which is a free program typically used to check CPU stability and (paired with something like Core Temp) its temperature.
For memory there is actually a built in memory diagnostic in windows 10 but it's not comprehensive, however I would still try this first. It's called windows memory diagnostic and it's very easy to use. It only runs for a short time, so afterwords I would recommend something more custom like memtest86 (old I know) because it lets you run tests for hours at a time, and if your RAM is not overclocked and truly working fine, it should pass even if left running for days.
The motherboard itself can also be hard to test since pretty much nobody has a spare lying around they can just swap out to see how things go. The same can be said for the power supply, so these can be sneaky and tricky.
ALSO - I should have asked this from the start, but if you are overclocked, revert to defaults before you attempt any of these tests.