try here.
http://users.erols.com/chare/cpu_sock.htm#socketa
11. I have a 462-pin (actually 453) Socket A motherboard. What can I upgrade to?
Socket A is a less expensive version of AMD's Slot A platform. It takes both the Athlon and Duron processors.
AMD Athlon 650, 700, 750, 800, 850, 900, 950, 1.0G, 1.1G, 1.2G, 1.3G, 1.33G, 1.4G (Thunderbird)
AMD Athlon MP 1.0G, 1.2G, 1500+, 1600+, 1800+, 1900+, 2000+, 2100+ (Palomino)
AMD Athlon MP 2000+, 2200+, 2400+, 2600+ (Thoroughbred)
AMD Athlon MP 2800+ (Barton)
AMD Athlon XP 1500+, 1600+, 1700+, 1800+, 1900+, 2000+, 2100+ (Palomino)
AMD Athlon XP 1600+, 1700+, 1800+, 1900+, 2000+, 2100+, 2200+, 2400+, 2600+, 2700+, 2800+ (Thoroughbred)
AMD Athlon XP 2500+, 2600+, 2800+, 3000+, 3200+ (Barton)
AMD Athlon XP 2000+, 2200+, 2400+ (Thorton)
AMD Sempron 2200+, 2300+, 2400+, 2500+, 2600+, 2800+ (Thoroughbred)
AMD Sempron 2200+, 2400+, 2500+, 2600+, 2800+ (Thorton)
AMD Sempron 3000+ (Barton)
AMD Duron 600, 650, 700, 750, 800, 850, 900, 950 (Spitfire)
AMD Duron 1.0G, 1.1G, 1.2G, 1.3G (Morgan)
AMD Duron 1.4G, 1.6G, 1.8G (Applebred)
Socket A has a layout that allows for 462 pins, but only has 453 pin holes to prevent the accidental insertion of an Intel Pentium III Celeron chip.
Mobile Athlon/Duron chips have a different pinout from other Socket A chips, and so are not compatible with existing desktop systems