Upgrade and Overclock a Xeon in a Mac Pro

Intel currently offers 2 FSB for Xeon 5xxx (Woodcrest). The most powerful (and expensive) Xeon feature a 1333MHz FSB, while the cheaper models have a 1066MHz FSB.
Our friend Tommaso from the Italian website o0o.it reports a procedure to force the bus of a Quad Core Xeon 1066MHz to 1333MHz.The processor initially clocked at 1.83GHz is then overclocked to 2.33GHz.
He was using the simple Pinmod procedure to achieve this overclock:

One "simply" needs to insulate one of the CPU contacts to overclock the processor. If the system does NOT visualize the increase of either the processor frequency or the FSB; it does work and the computer is indeed faster. One can then replace Dual Core Xeon by cheap Quad Core Xeon then overclock them to 2.33GHz, for a rather low price.