oh sorry, Its a laptop:
i7 720qm, ATI mobility radeon 4670
6GB ram, windows 7, java 64 bit
ive tried 2-4GB ram dedicated to minecraft also up to 512 perm-gen, fps goes from 30 to 1-2 in a couple minutes after I start playing, I'm using all low settings, have tried openGL on or off, same with...