A friend of mine had problems with his monitor, it would go into standby randomly when running certain games. I asked him for details about his setup and I was

A friend of mine had problems with his monitor, it would go into standby randomly when running certain games. I asked him for details about his setup and I was pretty confused when he said the connector at the back of his monitor had screws but I saw the Nvidia control panel reporting HDMI. Turns out he was using an HDMI to VGA adapter ! (GPU was outputting HDMI and screen consumed VGA). I just told him to go buy a display port cable (since his GPU and monitor both had it) and he had no problem since. Does anyone have insight about why the adapter could cause monitor standby in certain games ? It is really a peculiar issue.