Intel PT-6IBT User Manual page 34

440BX/ZX AT
Different Pentium™ II or Pentium™ III processors will use different FSB clock.
When you have installed the processor onto this mainboard, the system BIOS will
detect the type of the processor and decide the proper FSB clock automatically.
(Same as above, you can select other FSB clock in the BIOS setup program) For
detail information of your Pentium™ II and Pentium™ III Processor, please refer
to the CPU data sheet or confirm with your CPU dealer.
HOW TO SELECT THE CPU CLOCK RATIO:
Modify the formula mentioned in previous page and we will get:
CPU Frequency ÷ FSB Clock = Clock Ratio
Now we can use the formula above to calculate the CPU clock ratio. Please refer to
the following illustration for the calculation:
For example, if you are installing the 450MHz Pentium™ III processor onto the
mainboard. Suppose that you have known that the FSB clock for Pentium™ III-450
processor is 100MHz.
Now you may introduce these parameters into the formula and get:
450MHz(CPU Frequency) ÷ 100MHz (FSB Clock) = 4.5X (Clock Ratio)
According to the example above, you can refer to the switch setting table and find
the switch setting to select the proper CPU clock. You can see that it is very easy to
calculate the CPU clock ratio when you have the information of your information
of CPU frequency and its FSB speed. In order to let you have a better picture of the
calculation, the procedures are summarized as following:
1.
2.
3.
MAINBOARD
Check the data sheet for your CPU frequency.
Check the data sheet and get the FSB clock of your CPU.
Use the following formula to calculate the CPU clock ratio.
CPU Frequency ÷ FSB Clock = Clock Ratio
AWARD BIOS SETUP
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