if your computers is assholes
following my tips to increase increase
1.using grapmod
grapmod is make your gmod's graphics extremly low. so you can increase fps
2.multicore rendering
open your option you can see multicore rendering. but it just decoration.
so open your console
gmod_mcore_test 1; mat_queue_mode -1; cl_threaded_bone_setup 1
3.low your display
1024X1050
1024x720