Before starting to recognize which model of Athlon XP CPU you're using, do you know how many models AMD Athlon XP has? There are three models: Palomino, Thoroughbred, and the newest one, Barton. Please note that Thoroughbred CPU has two types of FSB speed, 266 and 333MHz.

OK, there is a simple way guiding you to identify your Athlon XP CPU model: