Why does my computer lose contact with my moniter since I have Windows 10?

[Windows Central Question]

After my computer has been running for a while - sometimes as short as 30 minutes, the screen suddenly goes dark and the monitor says it is going to sleep. Nothing I have tried will bring it back so I have to turn off the computer manually. So far it has come back when I booted again some hours later. The first time I disconnected the connecting cord and blew away any dust and reconnected. The picture came up when I booted up. The next I waited until morning and it came up again with a message saying to ask what a Memory Management Error was. I can find no info on that. Again it went dark and returned next day with no message at all. This only began happening after I upgraded to Windows 10. Is this happening to others?