Running Optifine 1.4.6 HD D5 in Ultimate SSP either makes the game a lot better, or makes it unplayable. When it works and the game loads correctly, it significantly improves framerate and makes the game playable for hours at a time (The nether is a deathtrap without it). About 60-70% of the time, however, the game grinds to a halt within a few seconds of the world loading--while the mod update messages are still popping up. It'll jump every 10 seconds or so but then immediately freeze again, and repeat no matter how long I wait, so I end up having to Force Quit.
Since it works sometimes I don't suspect my hardware specs are a problem, and I've checked that I'm still on Java 6. Sometimes when I've messed around with Java, it's right after that that the game will load correctly, so I will think I've fixed it, but then when I load the game up again later the lag will return for no apparent reason and stick around no matter how many times I try closing the game and restarting.
The debug screen doesn't usually say anything that indicates a problem---I always get the world leak messages even when the game plays okay. At least one time I had a repeating loop of messages about tick render problems or something, but I haven't been able to reproduce it.
Since it works sometimes I don't suspect my hardware specs are a problem, and I've checked that I'm still on Java 6. Sometimes when I've messed around with Java, it's right after that that the game will load correctly, so I will think I've fixed it, but then when I load the game up again later the lag will return for no apparent reason and stick around no matter how many times I try closing the game and restarting.
The debug screen doesn't usually say anything that indicates a problem---I always get the world leak messages even when the game plays okay. At least one time I had a repeating loop of messages about tick render problems or something, but I haven't been able to reproduce it.