Supply VS. Demand. Nothing more. I don't know for sure, but I would assume that AMD is still producing Athlon C's, but in very limited quantities. When the C's came out, the price of B's rose. Go hunting for a 1GHz B Athlon if youcan find one and see how expensive it is. Ridiculous in my book, especially since you can get a higher clocked C Athlon for less. but that's the way it is.