General Discussions

[Kiznaiver27]

The graphics card stops working at any time, whether I'm just browsing the internet, playing games or just starting up the computer.

I restart the computer and in dxdiag it says that it is using the motherboard graphics.
Restarting the computer reuses the graphics card.

But still after x time the screen goes black again, audio is heard and sometimes I can turn off the computer using command lines with the screen off or using Alt + F4, but other times it doesn't work.

What can I do to solve this problem?

CPU: i5-9600k

RAM: 16GB

[Vynski]

You never mentioned the brand and motherboard model you are using.  Due to the error you are getting after restart it sounds like one with integrated graphics.

Enter your BIOS; press the delete key on startup.  You may have to wait a second or two before you press it.

Select the SETTINGS tab and find the graphics and disable it.

[ThreeDee]

what power supply make/model are you using and how old is it? 

Have you tried testing with a different power supply?