Minecraft Forums

So, recently I had to do a clean install of win7 64. Before this, I could run minecraft flawlessly, around 90-100 fps on far render using 64x textures. Now, after the new install, I can play for anywhere between 1 and 10 minutes before the FPS just instantly drops off to <10. I don't know why this is happening because it's never happened before, and it seems to only happen on servers. I am using 64 bit java, and the only mod I have is optifine.