AMD World has posted a performance comparison between the KT266 and the KT266A chipset

Since I am now in possession of both a version 2 (KT266) and a version 3.1 (KT266A) Shuttle AK31 motherboards I thought it might be interesting to directly compare them, especially the memory bandwidth. When VIA first released the KT266 chipset there was widespread criticism of the memory bandwidth of the chipset, with most people reporting figures only 10% or so better than the older KT133A chipset. This meant that there was little point in upgrading to DDR for most people. Soon enough AMD came along with the 760 chipset which showed that it could be done, giving VIA even more incentive to improve the KT266's performance. They did however have one major handicap: most big board manufacturers had already tooled up for the KT266 set so any revised version would need to be drop-in - that is, use the same pin outs, BIOS codes etc. And revise it VIA did, coming out with the KT266A chipset. Which brings me back to the two boards I have here.

Read more