I tried to disable sync to vblank but it didn't change much. Since I use the an AMD Radeon GPU with the Gallium3D r600g driver I used the following command to switch off sync to vblank: vblank_mode=0 ./thedarkmod.x86 I also confirmed that this actually works on my system by running glxgears with and without the prefixed statement. Like I said I couldn't really tell the difference. Still very long load times on first load. When I hit the key with the ` and ~ in the upper left corner of my keyboard just below the escape key, I read the message that the VRAM will default to 64mb. By adding +set sys_videoRam 512 to ./thedarkmod.x86 I was able to use the full amount of VRAM. However, that didn't change much or the game experience or loading times.