Athlon model 8 and 10 default FSB
The L12 bridge communicates the default FSB speed to the motherboard. There is
usually no reason to change it, as most motherboards support ignoring of the
default FSB anyhow. However, there are some reports that for chips with a
default FSB of 166MHz, changing it to 133MHz allows higher FSBs to be used.
The bridges can be rejoined or the cuts can be filled with a conductive
material. The available L12 bridge configurations are: