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When Mixed Reality Portal is loaded, PC/screen freezes every 2 seconds and Acer hmd is off/black

I've reinstalled MR several times but this problem still persists. MR used to work fine for me about a month ago.
When I switch the ports on my GTX 1080 GPU around (hmd into the screen's previous slot), the hmd starts working but then the hmd starts freezing instead of the screen (with the PC screen suddenly working fine). It freezes consistently after about 2 seconds for about half a second and renders using both my monitor and hmd impossible.
I'm not sure what's happening but only Generic PnP Monitor appears in display adapters but at one point Mixed Reality Headset was there, once second in the list and another time first with the same problem but now it's gone. Perhaps the freezing is caused by Windows mixing the hmd and PC screen up but I'm not sure. I've no idea why it's not detecting the screen at all but the strangest thing is the constant freezing.
My OS build is 16299.251 and my Windows version is 1709.
(Initially I reinstalled my GPU drivers because ever since recent windows updates whenever I loaded the portal my screen would go black but that doesn't occur anymore. I've reinstalled my GPU drivers and the hmd works on other PCs/installs of Windows. Reinstalling my PC is not really an option as I have a lot installed on my computer.)
Answers
Please refer to : https://docs.microsoft.com/en-us/windows/mixed-reality/enthusiast-guide/troubleshooting-windows-mixed-reality#the-view-in-the-hmd-is-completely-frozen
and
https://docs.microsoft.com/en-us/windows/mixed-reality/enthusiast-guide/troubleshooting-windows-mixed-reality#the-world-briefly-froze-and-perhaps-tilted-or-flipped-upside-before-returning-to-normal
None of those describe what I have or fix the problem and I read all such before posting here. I've rebooted my device plenty times, reinstalled MR, etc. Though what's even stranger is this happens out of random but it's not the HMD. Windows appears to be confusing the screen outputs and causing the GPU to stall regardless of the GPU I do use. My PC worked fine with VR before and my specifications are more than adequate. This seems to be induced by the OS as I've checked that the GPU drivers haven't changed. Resources aren't peaking at all when the freezing occurs, freezing occurs every 2 seconds until the portal is closed.
I was actually able to trick Windows to not do this by using a splitter to copy the HMD output twice and only one output was freezing so I figure Windows is perceiving two main monitors, the HMD and my PC screen which is wrong. Though I can't get it to work again at all at the moment. I'm fairly certain the bug is Windows mixing the outputs up. Otherwise, I've no clue.
As an update, I can say that the HMD works fine when I have no screens plugged in but just the HMD but plugging multiple monitors in works fine so it's not a video memory issue it seems. I tried plugging in another HMD, the same issue occurs. So I'm pretty sure this is definitely Windows mixing the screens up. Though I really can't use VR with my screen off with Steam and other things, also the Desktop doesn't appear in VR when I have no screen plugged in for some reason.