It means altering the FSB, and other things in Bios, letting the CPU run at a higher speed. If your lucky you may get a few more Mhz, but more likely the CPU will fry, I accidently fried one in seconds. The potential gain is, in my opinion, not worth it.
It is possible, given the motherboard and BIOS support it, to run the processor faster than the rate it was sold as. This is overclocking. The manufacturers test each unit to see at what speed it will run reliably (within some design and manufacturing limits)and package it for sale. With 35 million transistors on the chip and a difficult process, this improves yield, price and profit.
HOWEVER, overclocking can kill the chip (faster equals hotter) and makes the warranty VOID.
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