Windows 10: Gaming labtop lagging without monitor connected to it

My labtop used to run fine and play some games and get over 70 FPS now when I unconnect it from my monitor it lags I’ve been searching for a fix but can’t find one I guess n one has the same proble.

Let me get this right: You want to disconnect a secondary monitor from your laptop and want to use the laptop screen instead, but when you do games starts to lag? What laptop is this?

MSi gt60 dominator 2pc

Do you use a power cord at all times, or the battery? Power-saving modes will be turned on if you use it as an actual laptop, so make sure it's plugged while playing. Open the Nvidia controlpanel (right click on desktop) and under Manage 3D setting will be a drop-down menu for your graphics processor. Choose Nvidia if it's on auto.

Power cord, already did that and I set it to high performance

And no dice? Is the screen resolution the same on both monitors? I mean is it possible that the monitor you used had a lower resolution and made games run better, while your laptop makes it a bit harder for them because it runs in higher quality? What games do you have this issue with anyway?

Rust,pubg