Expected Behavior

I have a low end PC, so i installed this mod, before that i used optifine but it works perfectly with around 25-30 FPS.

Actual Behavior

After I installed this mo i got only 0-5 FPS, which is very bad =(

Lithium doesn't really do anything to improve your FPS.
Lithium optimizes Minecraft's server performance so that it performs better.

@Nigelrex I would recommend also installing Sodium because Lithium optimizes server performance like Dbl7id said, while Sodium optimizes the game's rendering which should improve your fps.

@Nigelrex I would recommend also installing Sodium because Lithium optimizes server performance like Dbl7id said, while Sodium optimizes the game's rendering which should improve your fps.

I tried that also still 0-5 FPS =(

Was this in a new singleplayer world or was it pre-existing? Also check that you have your graphics settings turned down. I also recommend that you lower the opengl version of Sodium if your gpu does not support opengl 4.3.

Try using a lower render distance. Some users noticed that Optifine lowers the renderdistance (without changing the render distance setting) on their computer.

This is a support inquiry, not a bug report. Use the official Discord server to get help.