This solution worked on a Windows 10 machine with multiple monitors and GPUs.
After a Windows 10 update that replaced my Nvidia graphics drivers, Windows booted to black screens. Various other fixes failed.
- Boot to Safe Mode
Win10 is fast, so getting into safe mode blind can be tricky. Even if you turn fast boot off in the BIOS, if you have the OS on an SSD, the f8 key may not get you in.
- To work around this, hit the reset button on your computer case when Windows starts to load.
- On the 4th attempt, Windows should begin Automatic Repair (see Option 6 on digitalcitizen).
- Let Windows diagnose your PC.
- An Automatic Repair Screen will appear.
- Choose Advanced Options.
- Choose Troubleshoot.
- Windows will reboot.
- Choose Advanced Options >Startup Settings 5 or F5 to start in Safe Mode with Networking. This will put you into VGA mode and allow you to download files.
I used Clean and Restart and made sure that the app was set to turn off Windows Update for the graphics drivers.
- Allow the driver installation to reboot.
You should have your screens back, though you may need to check your display settings. In my case, I had to reorder the screens and rechoose the main monitor (Right mouse click > Nvidia Control Panel
- Geforce Experience will alert you to driver updates – check your settings
To keep Windows 10 from automatically updating device drivers, you might try modifying the registry.
- Instructions can be found here.
Or you may simply want to delay Windows update to ensure you install the graphics drivers from the manufacturer. This may not guarantee the drivers won’t be replaced by Windows.
Settings > Windows Update > Advanced Options