Suddenly blank screen in 19.1

Hi all,
today my system stop to work properly, suddenly it freezes the viewers and if I try to change tab (from Edit to Color) everything goes blank: viewers, timeline thumbnails, media pool thumbnails.
Restarting the app makes it work again for a few click, then it freeze again.
The only thing I've done this morning was to activate the "fixed playhead" option. After the first freeze I deactivated it, but the app is still stuck with this issue.
It's not related to a specific project: if I open what I've worked on yesterday it stucks after a few click as any other project.
Do I have to reinstall Resolve from scratch? Do I have to downgrade to 19.0.x?

It happens on the PC B on my signature, that's my main machine now.

What GPU driver version are you using?

What GPU driver version are you using?

I've updated to the last one, but it still freezing after a couple of click. I've unistalled the 19.1 and downgraded to the 19.0.3 with no luck.
Right now I'm working on the PC A that is in my signature, but it's really slow.
I'm working on color restoration of 14 documentaries on ancient Rome, with the cinematography of a well known DP.
Footage is ProRes 422 4K 24fps.
Tomorrow I'll see if by chance something has come loose, the RAM or the video card, because I have no idea what could have happened.

Terms like "latest", "newest", etc. don't really mean much. Especially to readers down the road. You should always be specific about versions.

today my system stop to work properly, suddenly it freezes the viewers and if I try to change tab (from Edit to Color) everything goes blank: viewers, timeline thumbnails, media pool thumbnails.
Restarting the app makes it work again for a few click, then it freeze again.

If you're encountering freezes and crashes, go to the Help Menu and select "Create Diagnostics Log on Desktop." If you're running Windows, create an NFO file by using the MSINFO32 command in the Start menu. Place both files on a download site like Dropbox, post the link here in a forum message and see what support has to say.

It also helps to provide information about your specific system -- CPU, GPU, RAM, disk I/O, operating system -- and also what specific files you're trying to use within the project.