1MB cache instead of 512 KB means your processor can have the data fast from the cache in 93 percent of the time instead of 90 percent.
Just saw, xp2400 has 246KB cache, then the rate is 85 to 93. Now missing the cache is not all that bad... costs some cpu cycles in theory but not that bad.
There is a theoretical speed up but it depends on the application how hard the hit is.
For AH or any other application speed ups below 30% are barely noticeable. So yes, its faster with more cache. Yes, there will be people talking of no noticeable speed up in jump from xp2400 to 64-3700. This doesnt mean there is no gain, this means when you up your resolution and quality sliders your can easyly overcompensate the improvements in the game and see none.
The 1MB cache itself gives little gain compared to 512kb unless if you use an application where its main loop + the data fit in 1MB but not in 512kB. With each cache miss you loose a little time, so haveing 3 percent less misses gives you 0.5 percent performance increase maybe.
The higher clock rate of the new chip, faster memory, new sse3 instructions if used, better jump prediction, less cache misses, better pipeline give the speed.
