a "deep rooted" problem

[VoidLord]

Whenever I go too far down my computer makes my game lag like crazy, knocking down the frame rate to about 2-3 per second, and it's horrible. If anyone could help with this problem it would be much appreciated because all the good minerals are just starting to emerge at this level.

[sfan5]

Try going far down, logging out and logging in again.
That could fix it until you go up again

[PilzAdam]

Do you use my nether mod?

[VoidLord]

sfan5, I've already tried that a long time ago and it didn't work.
PilzAdam, no, although I do have so many mods it takes the game 2 minutes to boot.

[nolan]

If u still have this issue, do u have shaders check marked in setting? un check shaders if so they can create horrible lag..

[Casimir]

although I do have so many mods it takes the game 2 minutes to boot.

Maybe this is where the problem is. Disable all and try if it still lags. When everything works fine you can enable one after the other until it lags again. Then you know what mod is causing the problem.