Asus SP97 - Manual (Page 17)

ASUS SP97 / SP97-V User’s Manual 17
III. INSTALLATION
(Jumpers)
III. INST
ALLA
TION
3. CPU External Frequency (BUS) Selection (FS0, FS1, FS2, FS3)
These jumpers tell the clock generator what frequency to send to the CPU. These allow
the selection of the CPU’s external frequency (or BUS Clock). The BUS Clock multi-
plied by the BUS Ratio equals the CPU’s internal frequency (the advertised CPU speed).
When BUS Frequency is set to 75MHz or more, the PCI Frequency Selector
(FS3) must be set to asynchronous PCI mode to maintain PCI signal stability.
4. CPU to BUS Frequency Ratio (BF0, BF1, BF2)
These jumpers set the frequency ratio between the internal frequency of the CPU
and the external frequency (called the BUS Clock) within the CPU. These must be
set together with the jumpers for CPU External (BUS) Frequency Selection.
CPU External Clock (BUS) Frequency Selection
CPU : BUS Frequency Ratio
P54C/K5
P55C/K6/MX
IBM/Cyrix 6x86
1
2
3
Complete Names:
Intel Pentium P54C, P55C-MMX
AMD K5, K6
IBM/Cyrix 6x86(M1), 6x86MX(M2)
R
1.5x(3/2)
3.5x(7/2)
3.0x(3/1)
BF1 BF2 BF0
2.0x(2/1)
2.0x(2/1)
2.0x(2/1)
BF1 BF2 BF0
2.5x(5/2)
2.5x(5/2)
1.0x(1/1)
BF1 BF2 BF0
3.0x(3/1)
3.0x(3/1)
4.0x(4/1)
BF1 BF2 BF0
----
4.5x(9/2)
----
BF1 BF2 BF0
----
4.0x(4/1)
----
BF1 BF2 BF0
75MHz
1 2 3
FS1
FS0
FS2
FS3
1
2
3
66MHz
1 2 3
FS1
FS0
FS2
FS3
1
2
3
60MHz
1 2 3
FS1
FS0
FS2
FS3
1
2
3
50MHz
FS1
FS0
FS2
1 2 3 FS3
1
2
3
Sync Sync Sync ASync