Not true. YOu need to get your facts straight before you mess people up.
A Barton IS clocked slower, but the L2 cache does nothing really. In other words, the Barton 2500 clocked at 1.83 is obviously slower than the 2400 at 2.0. Now if you overclock the Barton 2500 to 2.0, it then MATCHES the 2400 in speed, despite the L2 cache being larger. The Barton, even with large L2 cache, WILL NOT perform better than the 2400 until you clock it HIGHER than the 2400. But this goes for any athlon vs. any athlon, so the L2 cache really makes no difference.
You may be stupid, but even you should remember the little alligators from elemtary school:
Here is the speed comparison:
Barton 1.8 < 2400 2.0
Barton 2.0 = 2400 2.0
Barton 2.+ > 2400 2.0