CPU multiplier

Trinity processor model numbers which end with the letter "K" denote processors with an unlocked CPU multiplier.

Many overclockers, however, had been able to overclock the core to 4.26 GHz using air cooling simply by raising the unlocked CPU multiplier.

Most modern CPUs increase their effective operating speeds by multiplying the system clock frequency by a factor (the CPU multiplier).

Different CPU speeds are achieved by varying either the FSB frequency or the CPU multiplier.

Electronic circuitry translates that into a square wave at the same frequency for digital electronics applications (or, in using a CPU multiplier, some fixed multiple of the crystal reference frequency).

In computing, the clock multiplier (or CPU multiplier or bus/core ratio) measures the ratio of an internal CPU clock rate to the externally supplied clock.

Generally, the lower the CPU multiplier (and thus clockrate of a CPU), the closer its performance will be to that of the bus, and the less time it will spend waiting.

CPU multipliers, bus dividers, voltages, thermal loads, cooling techniques and several other factors such as individual semiconductor clock and thermal tolerances can affect the speed, stability, and safe operation of the computer.

Super Socket 7, which increased the processor bus from 66 MHz to 100 MHz, allowed the K6-2 to withstand the effects of ever-increasing CPU multipliers fairly gracefully and in later life it remained surprisingly competitive.

One of the most important techniques is running at a higher clock rate (more clock cycles per second; hence the name "overclocking"), but other parameters, such as CPU multiplier and memory timings, can also be changed and would be considered to be overclocking.

CPUs can be overclocked by manipulating the CPU multiplier, and the CPU and other components can be overclocked by increasing the speed of the system clock or other clocks (such as a front-side bus (FSB) clock).