Framerate drop with new monitor troubleshooting

I recently upgraded my monitor from a 75hz 27’ HDMI connection to a 32" 240hz DP and now my retro games are giving me terrible framerates, for instance Aliens vs predator 2 is giving me about 10fps. I have it modded to play at 1080p which worked perfectly on the old monitor but not the new one.

Is there a setting a need to tweek in lutris to get this running smoothly again?