Thoroughbred is just die-shrink
As AMD has now announced, when moving from the polomino core of the current Athlon XP to the Thoroughbred core, only the die size is reduced by the 0.13 µ manufacturing process, otherwise no changes are made to the core itself.
However, this allows AMD to reduce the power consumption of the processor and produce more CPUs from one wafer, which should have a positive effect on the price. Furthermore there will be the K7 and K8 Hammer CPUs, which means that socket A will also be available until at least 2003, so that the socket would then be present on the market for 4 years. It is not yet known exactly when the new Thoroughbred CPUs will come onto the market; CeBit 2002 is mentioned as a possible date. That would be at the same time as the VIA KT333 chipset with 166 MHz FSB, which suggests that the new AMD CPUs will also support this bus clock.