Thread:LOTRMod/@comment-73.39.101.60-20140710172321/@comment-25565811-20150218114748

The makers of the optifine mod recommend even less (500-700 MB) they say that way your computer is able to swap memory easier to the hard drive.

My MC installation with lotr mod, fastcraft, optifine, bibliocraft and mapwriter uses about 1 GB of space and runs quite smoothly (as long as the server runs smoothly).