As the title says, whenever I change to ANY version besides 1.8, I crash. I can't tell why, but since my laptop runs very slow when I go on single player, it does this when on multi-player. Can someone help me with this? Also, I do have a mod installed.. But this is on unaltered versions like 1.7.10, 1.7.5 and so on.
Old versions don't support the large render distances that 1.8 supports.