Hello David573.
Welcome to Microsoft Community.
Regarding to your information I assume that your monitor will lose connection to the PC and pc crash when you run any 3D programs.
Did the sound still play after the monitor lose the connection?
From my experience, it looks like the Graphic Card Driver crash or your Graphic Card has some hardware problem caused.
To better identify the cause, please check if there are any relevant logs before the black screen occurs.
Could you provide the Event Log before your monitor lose the connection?
Search Event Viewer.

Check the log before losing the connection and please upload it to your convenient cloud driver.
You can also check it in Reliability Monitor and please upload it to your convenient cloud driver.

Before getting the log please make a test that tries to press Ctrl+Shift+Win+B to restart the Graphic Card Driver.
If there is anything not clear, please do not hesitate to let me know.
Best Regards,
Tommy-MSFT | Microsoft Community Support Specialist