When I play the new ftb ultimate(the one with 120 mods) i get about 100 fps but after about 5 sec it will freeze/ fps drops to 1 and then jumps back up to 100. this happens continuously when I play occurring every 5-10 seconds. I have 6 GB of RAM allotted and it doesn't even use all that, my graphics card can play Crysis 3 high settings(hd Radeon 7500) no problem so that's not it and my CPU is an Intel i5-3750k at 3.6 ghz. Optifine doesn't seem to help, if anyone has any suggestions that would be helpful.