Hardware Reference
In-Depth Information
Forexample,sayyouhaveaSocket775motherboardrunninga2.4GHzCore2Quadpro-
cessor at a CPU FSB speed of 1,066MHz. The motherboard permits 1MHz adjustments
of the CPU bus clock speed (which is multiplied by 4 to obtain the FSB) to enable you to
fine-tune yourprocessorspeed.Thebaseclock frequency is266MHzandismultiplied by
4 to obtain the motherboard bus (FSB) speed, which is then further increased by the CPU
multiplier:
800MHz × 3.5 = 2,800MHz, or 2.8GHz
By adjusting the CPU clock frequency, you can change the FSB and CPU core clock
speeds as shown in
Table 3.25
.
Table 3.25 Core Clock, FSB, and CPU Speed Relationships
As you can see in this example, by increasing the base clock from 266MHz to 300MHz,
you increase the FSB from 1,066MHz to 1,200MHz, and the CPU core speed from
2.4GHz to 2.7GHz, nearly a 13% increase. Typically, increases on the order of 10%-20%
are successful. You might be able to achieve more if your system offers excellent cooling
and you can also adjust CPU multiplier, voltage, and other settings.
