K7T Pro/Pro2/2A: KT133, green PCB. 6 PCIs, RAID n/a, FSB 100-166
K7T Turbo: KT133A, green PCB, 6 PCIs, optional RAID, FSB 100-166.
K7T Turbo Limited: KT133A, red PCB, 6 PCIs, optional RAID, FSB 100-199, PC2PC(MSI LAN)
K7T Trubo2: KT133A, red PCB, 5 PCIs, RAID n/a, FSB 100-199, D-Bracket(D-LED combined with a USB riser)
The three KT133A varieties don't differ from each other too much at all, all three were derived from the original K7T Pro. The Turbo and Turbo Limited are virtually identical motherboards, except the Limited edition is red, has more extras and goodies, and a wider range of FSB selections. The new Turbo2 is designed to cut cost, with a smaller board size, less PCI slots, no RAID option and almost no extra goodies; but interestingly, the Turbo2 was the best performer of trio. Also remember that Turbo and Turbo Limited can only support AthlonXP up to 1800+, while the newer Turbo2 is able to support 2000+(2100+ and 2200+ possible).