VR-Zone has done up an KT133A upgrade guide for those thinking of upgrading
their system now where AMD currently offers the best performance/price
ratio. We have compared KT133 against a KT133A with different FSB
combinations and show how the performance differs. It provide some guidance
when you are thinking of upgrading your present system and how you should
set your FSB to obtain optimum performance.
FULL STORY @ VR-ZONE (http://www.vr-zone.com/guides/kt133upgrade/)