I recently downloaded the 64x version of LB PhotoRealism just to see if my computer could run it (My computer sucks at being a computer). Very surprisingly, it could run it, and in fact, I got a higher framerate and less overall lag on both singleplayer and multiplayer when using LB PhotoRealism than when I was using the default 16x texture pack that comes with minecraft. Do any of you have any idea why any 64x texture pack would run better on a crappy computer than the default texture pack?
Also, do any of you know any good lag-decreasing (8x, 4x maybe?) texture packs that still look good? Even with LB PhotoRealism's strange lag-reducing powers, I still lag a lot.