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Friday, April 4, 2008

CPU Overclocking

Overclocking CPU is a process to increase the GHz rating of the CPU. The formula to calculate the speed of the CPU is as follows - The product of the FSB in MHz and the multiplier is the speed in MHz.

FSB

The FSB is a short form for Front Side Bus. CPU manufacturers have detected a method to raise the effective speed of the FSB. This is done by just sending more instructions per clock cycle. Thus, in every clock cycle, sometimes two or four instructions are sent. This results in increasing the FSB twice and four times respectively. This is of utmost significance. The reason is that when overclocking of the CPU is done, the user deals with the real FSB speed of the CPU and not the effective CPU speed.

Multiplier

This is simply a number which when multiplied by the FSB speed results in the total speed of the CPU. For example, if there is a CPU that has a FSB of 300 MHz and a multiplier of 10, then the CPU speed becomes 3000 MHz or 3.0 GHz. In case of CPU's like the Intel CPU's since 1998, the multiplier is a fixed number and cannot be altered. On other CPU's like the AMD Athlon 64, this number is top locked. What is implied is that the multiplier can be altered to a lower number but cannot be changed to a higher number. In case of some CPU's, the multiplier is totally unlocked. In this case, it can be changed to any higher or lower number. This is suitable for the overclocker.

It is simpler to overclock the system by raising the multiplier rather than the FSB. The reason is that the multiplier affects only the CPU speed. Raising it means overclocking the CPU. However, if the FSB is altered it amounts to changing the speed of each single component that communicates with the CPU. Thus, this means overclocking all the other parts of the computer system as well. This can give rise to a number of problems. The components that are not meant to be overclocked are forced to do so and may fail to perform.

AMD Athlon 64 cpu

In case of these CPU's, the term Front Side Bus is a misnomer. This is actually called as a HTT. These CPU's do not have a FSB. This term is integrated with the chip. Due to this the FSB communicates with the CPU at a higher rate than

Billy Zype is an overclocking expert. You can check out his website at http://www.hotoverclocking.com

 

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