Modded Minecraft is abysmal with GTX 970/I7 4790K

[UCFTyler]

As the title says, I am having a horrible modded Minecraft experience with a great PC. Without mods, I can play upwards of 900 FPS if I have unlimited FPS on. But the moment I use mods, specifically Life in the Woods or a Shaders modpack, my FPS tanks to anywhere from 20-60 FPS (I know there will be an FPS drop, but it is literally unplayable). I have seen people who have lower tier CPU's and GPU's running these at 100+ FPS, so what is my problem? I am running MC at 1920x1080, 144hz monitor w/ dual displayport, and specs are GTX 970, I7 4790K, 8GB RAM, and I can provide any other info needed.

 

[Th3R3ALaSSaSSin4]

Try getting the mod from another place.

 

[kunstderfugue]

It looks like the problem is on the side of the mods - possibly some that are incompatible or some that are clogging your resources by say, trying to load different parameters for the same object. Try disabling mods 1 by 1 to see which one's the one that causes performance problems.