erhhhhh....Durons aren't exactly well-known known for their overclocking capabilities.
Okay, that was an understatement.
They are notoriously difficult to overclock.
I would've said impossible, but i read somewhere that someone managed to squeeze an extra few megahertz out of a 1.3Ghz.
other than that, i would suggest shelling out $78-100 for an Athlon XP 2400-2600+ at www.tigerdirect.com
all three of the above are already much faster, and also have a much higher capacity for overclocking than any of the Durons.