Windows crashed a lot with black screen  

Nvidia has been known to have its own update procedure. Not clear on that.

All we know at present is that you didn't get an update for it via Windows Update.

Now see if you have any significant crash reports. Have a look at your Reliability History and inspect any red x's that correspond to the time when you had a crash. Example:

Ah, sorry, the language/unfamiliar presentation meant I missed the update in your post #11.
So you had an Nvidia update on the 6th of Feb which might be related to what you're seeing, but you don't have a rollback option.

That gives a version number 27.21.14.5671.

You post #7 says you can't download a compatible Nvidia driver.

at this point you might try posting on an Nvidia forum to try to find out how to get a compatible driver- I've not seen a problem of that sort before.

I suppose you might even try a driver updater tool such as DriverMax to see if it can locate one. Normally the use of such tools is not recommended.

You could try this:
NVIDIA Driver Downloads - Automatically Detect NVIDIA Products
- but you may need to consider the site/language used.

Or you could try this:
Download Drivers | NVIDIA
- noting you can select the language.



Then select your 1660ti
then your language.

Ideally you would be able to find an older build than that downloaded. I have no suggestion about your compatibility problem other than the above.

First bear in mind you'll get the latest driver available via Windows Update after a clean install. That my be later than the previous one you had installed.

Second, the Tutorial section has 100s of useful tutorials
Windows 10 Tutorial Index
e.g.
Turn On or Off Device Driver Automatic Installation in Windows 10
Prevent Windows Update from Updating Specific Device Driver

There was a specific issue with Nvidia about a year ago or more when nothing would stop a particular Nvidia update being delivered.

You will probably find Windows doesn't include the Nvidia driver - that needs to be downloaded one way or the other.

As such, it would be good to try again to find a compatible driver you can download. Normally people can find older drivers for Nvidia.