In general, your laptop comes with two GPUs for the better performance and power saving. When you run power-intensive apps like games, system will use the discrete GPU. The integrated GPU is mainly for low-power apps running. You are more likely to get the OBS game capture black screen problem if system uses the low-performance GPU for the game and OBS recording.

When you only get a black screen in the OBS recording window, no matter what capture mode (Game Capture, Window Capture or Display Capture) you are using, you can try switching the OBS’s GPU for the fixing.

Step 1: If you only see a black screen in OBS, you should first close it.

Step 2: Back to the desktop window on your computer and right click on the blank space. From the drop-down list, choose the “NVIDIA Control Panel” option.

Step 3: When you enter the “NVIDIA Control Panel”, click “Manage 3D settings” on the left panel. Choose the “Program Settings” tab on the right window, and then click the “Add” button next to the “Select a program to customize” option.

Step 4: Click Browse and then locate the OBS.exe. Right click on its icon and choose the “Open file location” option. Then select the “High-performance NVIDIA processor” and click “Apply” to confirm the operation.

Step 5: Close the “NVIDIA Control Panel” window and then restart OBS to check if the OBS game capture black screen problem is gone.

4 Simple Ways to Fix OBS Game Capture Black Screen: https://www.vidmore.com/record-game/obs-game-capture-black-screen/