As of recently I got athlon +2800 xp and a asus 17n8x-x motherboard. From knowlage from sources it is said that it's actualy speed is 2.2GHZ. When my computer starts up it says its 1.25Ghz along with some other useful tools that tell your computers speed. Maybe i misunderstood what the sources said and its suppost to run like 2.2Ghz, but i had this problem before with my athlon +1800 xp.
My system-
Athlon +2800 xp
Asus A7N8X-X
Gforce FX 5200 128MB ram
SB Live.
785DDR 333