PC keeps going to standby upon turning on

Hey there guys!

My PC all of the sudden started to show "Standby" mode on screen when I try to turn it on, so it won't even load windows, show welcome screen or anything. I can go to safe mode though, and from there I did a recovery from a 10-ish days old backup, which resulted in exactly the same situation: I again have the same standby mode upon turning it on, and can't go to OS.
After that, I used reinstall option with saving my files, used download pack from internet to reinstall Windows, and when that finished - again the same standby mode!
I lost my mind last night and went to sleep, trying to think through what would be the next steps to perform today, so any suggestions maybe?

The PC was bought like 6 months ago, parts were connected and it's working since then without a problem. I'm out of ideas about what to do next apart from completely remove OS and install it all over again from usb or something, though I'm afraid that that won't fix the problem as well. Note that monitor is working okay, since I used it in safe mode, and it's not going to standby, so it's not monitor related.

Thanks!

Thanks for your answer!
I'm not aware that any new software is installed, I used it like usually, and I'm not sure that windows updates were installed though it's possible. However, when I did a restore that should be reverted, and I still get the same problem, so that's why I'm worried.
I will try with new user account new, though I don't think it will help, as I can't even see login screen with accounts when I try to turn the PC on, it just shows standby mode, and then the screen goes black, so I can't see user accounts.

PC is custom built, here's the setup:

AMD Ryzen 7 38000,
graphic: Nvidia Quadro p2000 5GB
RAM: KINGSTON HyperX Fury RGB 16GB (2x 8GB) DDR4 3200Mhz
MB: Gigabyte B550M DS3H
HDD: Patriot SSD M.2 2280 1TB
PSU: Seasonic S12III Bronze 650W

I bought the parts and connected everything about 6 months ago, everything worked just fined until now..

Thanks for your suggestion, I really appreciate it! I will most definitely try that today. Not really sure which drivers were previously used though as it was automatically downloaded through the windows drivers interface, but I'll report here whether that helped!

I had to reinstall Windows again.
Downloaded and done installation and when windows update finished it again showed the same problem. Looks like really some of the updates is having a problem with this driver.

I reverted latest update so it's working again, but with no driver, so it's all messy.
Also the official NVIDIA driver from their site (link posted above) is not working for some reason.
Screenshot attached.

I had my internet connection turned off while installing it, and I turned the internet on when installation was done. Then I used device manager to update only drivers I want, and not graphic driver. Now I can use the PC, but screen resolution is not right, and everything looks odd and low-res because i have no display driver installed. Now I'm not sure what to do next though.

Thanks!
Just wanted to report back.
I tried everything you suggested, tried with DDU, but still got the same result when installing the driver. Tried a few different drivers from their official site as well. I tried their NVIDIA uninstall tool to remove all drivers and re-install what I want again, and still the same result.

The last thing I tried is to ask for their support for suggestions. and after an evaluation, they suggested that I physically remove the graphic card and change the port where it's connected to the motherboard. I will try that tonight, though I don't see how that may help.