You're going to need to boot from a live CD (like Ubuntu or Mint Linux), copy your data to a flash drive or external hard drive, then restore to factory settings. If you had a full system backup, you could be back up and working in 30 minutes, but unfortunately you're into the pound of cure since you didn't use the ounce of prevention.
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Good luck.
I recently was fiddling with my graphics card for coin mining, moving them around, modding, etc. when windows decided to essentially shut down all services; aero stopped working, no internet, sound, even system restore wouldnt work naming a Volume Shadow Copy error (still wouldnt work after turning the service on). I actually had this same problem on another computer before and simply did a system restore through the boot up 'repair my computer' recovery tool.
However, this does not work for my desktop. The files load, I see the little green microsoft loading bar and even the first page of the blue background recovery screen only to have it crash a few seconds later. Computer just shuts off and turns right back on. This exact problem occurs even with a windows recovery disk. It seems as the problem persists through every form of recovery. I also tried all safe modes with successful booting but none allow for system restore.
NOTE: When I was working with the graphics cards I did use a bootable usb drive with win98 dos. Both of my two graphics cards work fine individually yet using either the crashing problem continues.

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