External monitor no longer works after configuring a game

[capricorn2002]

Hello.

I have been using a second monitor with my laptop for a long time. There has not been an issue with it until now. I launched Star Wars Battlefront 2 for the first time and did the whole setup routine, including selecting which monitor to use. Seems like that'd be super simple and not a problem.

However it started bugging out when I selected the external monitor. That was weird and I still don't know why but I thought little of it and just used the main one and switched the external one off. The game ran well enough and it seemed like that was that. Even so, this required a restart and made loading extremely slow. Plus the results didn't look good enough to justify that so I just reverted it. 

The real issue came up after. When I exited and turned the external monitor back on, the problem remained. It just disconnects then reconnects in an endless loop to the point where I can't even use the laptop itself. The screens appear, then go black, then back and forth. So I have to keep the monitor unplugged to use my laptop at all..

The weird thing is that when I plug it back in, everything looks fine for a couple of seconds. But then goes right back to doing the same old thing.

I've tried restarting the system (multiple times), unplugging all the cables the monitor uses, as well as reinstalling my display drivers (then trying a couple of different older versions of the drivers). So far nothing has fixed it.

I have an older monitor and an older laptop and tested configuring each of them. The newer monitor (the one with the issue) works with the old laptop. The older monitor works with both laptops. It's just the newer monitor that has a problem with the new laptop. I'm convinced it's the game that caused this because it happened at that exact same time and nothing else had changed. I've never had any issue like this before.

The game was installed on an external hard drive, if that's relevant. I haven't installed many things on an external hard drive before but the few times so far have not caused any issues. I've since uninstalled the game.

I've never had anything like this happen, where a game can cause lasting effects on my system. So any and all advice is welcome.

Thank you.

Newer monitor:
Samsung - Odyssey 27” IPS LED QHD FreeSync Premium & G-Sync Compatible Gaming Monitor with HDR (Display Port, HDMI)

Older monitor:
Samsung - 390C Series 24" LED Curved FHD AMD FreeSync Monitor (HDMI, VGA)