Abit IT5 Series, User Manual

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Introduction of BIOS 3-7
Normally, we do not recommend that you use the
“
User Define
”
option to
setup CPU speed and multiplier factor. This option is for setup of future CPUs
whose specifications are still unknown. The specifications of all present CPUs
are included in the default settings. Unless you are very familiar with all CPU
parameters, it is very easy to make mistakes when you define by yourself the
external clock and the multiplier factor.
/
Turbo Frequency:
This item will only be displayed if your CPU external clock supports
Turbo mode.
The Turbo mode allows you to speed up the external clock by
approximately 2.5%. This feature is used to verify the design
flexibility. It is a very important tool for test units to verify CPU
stability. Do not use this feature.
ä
Disable: CPU external clock is operating within the
normal limits.
ä
Enable: CPU external clock is operating within the
limits of the Turbo mode.
Solution in case of booting problem due to invalid clock setup:
Normally, if the CPU external clock setup is wrong, you will not be able
to boot. In this case, turn the system off than on again. The CPU will
automatically use its standard parameters to boot. You can then enter BIOS
Setup again and set up the external clock.
When you change your CPU:
IT5 series mainboards have been designed in such a way that you can
turn the system on after having inserted the CPU in the socket without having to
configure any jumpers or DIP switches. But if you change your CPU, normally,
you just have to turn off the power supply, change the CPU and then, set up
the CPU parameters through CPU
SOFT MENU
™
. However, if the CPU
brand and type is the same, and if the new CPU is slower than the old one, we
offer you two methods to successfully complete the CPU change operation.