I don't know why minecraft runs too slow on my computer. My friends can run better than I on Intel CPU's. I have a Phenom II x4 3.0GHz working with a HD 7770 and I only can get about 65fps. While my friends are getting about 300fps on a Core 2 Duo 2.6GHz and a HD 6570. I really don't know why it's happening. My PC can handle with heavier games, except minecraft. It's really boring try to play a wonderfull game and depares with lag. I'm sad, because I've bought the game and I can't play it. I hope that Mojang fix that, I'm not alone. If you search on google "minecraft good specs low fps" you will see a lot of people with the same issue.