VIA 82C693
MAINBOARD
HARDWARE SETUP
3-18
(C) JP5-JP7:
CPU Speed Selection
SPKR
BIOS
KBLOCK
CN14
JP 5
JP 6
JP 7
CPU Clock
233, 350MHz
266, 400MHz
300, 450MHz
333, 500MHz
Ratio
3.5X
4X
4.5X
5X
JP5
Open
JP6
JP7
Short
Open Short
Open
Short
Short
Short
Open
Open
Open
Open
366MHz
5.5X Open Open Open
JP5, JP6 and JP7 allow you to select CPU clock ratio. .
Basically, there are two parameters which will decide the CPU speed - the Front
Side Bus (FSB) speed and CPU clock ratio. When you have installed the processor
on the mainboard, the system BIOS will detect the CPU type and decide the FSB
speed automatically (please refer to
section
4-6
.). As for the clock ratio for the
Pentium™ II processor, it is selected by the jumper setting on JP5, JP6 and JP7.
In other word, FSB will be used to decide what type of processor is installed on the
mainboard. JP5~JP7 will be used to decide the system speed. The following
formula is the simple rule to calculate your CPU frequency:
FSB Clock x Clock Ratio = CPU Frequency
SELECTION OF FSB CLOCK
( please refer to section 4.6 )
Different processors have the different FSB clock. When you have installed
the processor onto the mainboard, the system BIOS will detect the type of the
processor and decide the proper FSB clock automatically. The default setting
in BIOS setup program are:
66MHz processors:
Pentium™ II-233, 266, 300 and 333MHz: 66, 68 or 75MHz selectable
Celeron™ -266, 300, 300A, 333 and 366MHz: 66, 68 or 75MHz selectable
BIOS Ddefault
: 66.6 or 68MHz (depends on the clock chip on the mainboard)
