AMD DURON 700

There are two common techniques used to over clock a CPU.  The most common is to increase the FSB (Front Side Bus) of the motherboard.  Many motherboards have the ability to run at various bus speeds.  This can be adjusted by either jumpers or dip switches on the motherboard, or by menu in the BIOS setup.  The technique has been around for a long time and is always the choice when the CPU multiplier is locked. 

Most chips have their multiplier locked by the chip maker and this is not easily overcome on Intel chips but with the newer AMD flip-chips quite easy to do.  This is a good thing.  Since AMD chips double the bus speed (i.e. setting a 100Mhz bus in Bios yields a 200Mhz FSB, they are no where as near as overclockable as in INTEL chip if you were going to OC by FSB only.

In the above picture you can see the bridges that control the chips speeds and voltages.  The Upper right one is the infamous L1 bridge which locks the multiplier.  In this picture the four L1 bridges are closed and that makes this chip "unlocked".  If you look to the left of it at the L3 bridge you can see a fine dark line bisecting the bridge.  That cut is formed at the factory when a laser cuts the bridge.  If your processor has the L1 bridges cut (and most do) all you need to do is reconnect them to unlock the chip.  This requires a steady hand but a sharp #2 pencil or HB or softer drafting pencil can be used.  Simply draw the lines in, taking care to not cross connect any of the bridges.  The graphite is conductive enough to work.  If you are feeling particularly daring and handy you can also use a conductive pen, like those used to repair circuit traces on PCB's

Once unlocked and if your motherboard supports manually set multipliers you can simply start cranking up the Mhz.

WARNING    Yes time for the scare you warnings.  Overclocking any chip will cause it to run hotter.  Hotter chips fail sooner.  To get the chip stable at higher speeds it may be necessary to increase the voltage to the chip.  Guess what?  More voltage means more heat.  Proper and efficient cooling is mandatory if you plan to overclock.  AMD chips run much hotter than INTEL chips even when not overclocked, and they really put out the heat when you start tweaking them.  Also last but not least remember that overclocking your CPU VOIDS the warranty and it is quite possible to destroy the chip in the process.