Maybe is your first time playing the game or maybe you used to play it but drop it some time ago, but now you realize that if you try to change the screen configuration to anyone diferent to "window" you get something like this



or a full black one if you choose full screen.

There is already a guide to solution the problem if you are running the game on a laptop, (https://cs2bus.com/sharedfiles/filedetails/?id=687269832) but for desktop users, we dont have the option to use the integrated graphics. But doing a very similar steps we can fix this problem on desktop.

Go to Nvidia Control Panel


Then go to Program Settings on Manage 3D Settings


Now Select the Gunhound aplication from the list (if there is not in the list then click on the Add and find it)


Finally set Off/Disable in Antialiasing-Mode and click on Apply


After finished the steps the game should look like one of those

Now you wont get the black screen when you change the screen mode.

If you cant solve the problem only with those steps, try to set Off/Disable all the features on the program settings of the game in nvidia control panel, or at least set the features in order to have the GPU controling nothing of the game.

Some problems:
I realize that if you change the screen mode twice or more consecutively or in the same session, you get stuck on the game window. You can still play the game normally but you wont be able to change the window, if you use alt+tap the game window will be still on first plane (you have to choose the game window again or you cant do any action on the game). The only solution I could find was close the game.