Iii. installation – Asus P/I-P55SP4V User Manual
Page 16
ASUS P/I-P55SP4V User’s Manual
10
III. INSTALLATION
(Jumpers)
III. INST
ALLA
TION
5. CPU External (BUS) Frequency Selection (JP5, JP6, JP7)
These jumpers tells 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 times the BUS Ratio equals the CPU's Internal frequency (the
advertised CPU speed).
6. CPU to BUS Frequency Ratio (JP11, JP12)
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 above jumpers CPU External (BUS) Frequency
Selection.
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J
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Set the jumpers by the Internal speed of the Intel, AMD, Cyrix, or CPU as follows:
(BUS Freq.)
(Freq. Ratio)
CPU Model
Freq.
Ratio
(BUS Freq.)
JP5
JP6
JP7
JP11 JP12
Intel Pentium
200MHz
3.0x
66MHz
[1-2] [1-2] [1-2]
[2-3] [1-2]
Intel Pentium
180MHz
3.0x
60MHz
[1-2] [1-2] [2-3]
[2-3] [1-2]
Intel Pentium
166MHz
2.5x
66MHz
[1-2] [1-2] [1-2]
[2-3] [2-3]
Intel Pentium
150MHz
2.5x
60MHz
[1-2] [1-2] [2-3]
[2-3] [2-3]
Intel Pentium
133MHz
2.0x
66MHz
[1-2] [1-2] [1-2]
[1-2] [2-3]
Intel Pentium
120MHz
2.0x
60MHz
[1-2] [1-2] [2-3]
[1-2] [2-3]
Intel Pentium
100MHz
1.5x
66MHz
[1-2] [1-2] [1-2]
[1-2] [1-2]
Intel Pentium
90MHz
1.5x
60MHz
[1-2] [1-2] [2-3]
[1-2] [1-2]
Intel Pentium
75MHz
1.5x
50MHz
[1-2] [2-3] [2-3]
[1-2] [1-2]
AMD-K5
100MHz
1.5x
66MHz
[1-2] [1-2] [1-2]
[1-2] [1-2]
AMD-K5
90MHz
1.5x
60MHz
[1-2] [1-2] [2-3]
[1-2] [1-2]
AMD-K5
75MHz
1.5x
50MHz
[1-2] [2-3] [2-3]
[1-2] [1-2]
*Cyrix 166+
133MHz
2.0x
66MHz
[1-2] [1-2] [1-2]
[1-2] [2-3]
*NOTE: Only Cyrix Revision 2.7 or later is supported on this motherboard. See next page
for revision identification. Bootup screen will show 6x86-P166+ -S CPU at 133MHz with
the Cyrix 166+ installed on this motherboard.