INSTALLATION .III (Jumpers)

III.INSTALLATION

7.CPU External Clock (BUS) Frequency Selection (JP9, JP10)

These jumpers tells the clock generator what frequency to send to the CPU to allow the selection of the CPU’s External frequency (or BUS Clock). The BUS Clock times the BUS Ratio equals the CPU'sInternal frequency (the advertised CPU speed).

8.CPU to BUS Frequency Ratio (JP12, JP13)

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.

JP10

JP9

JP10

JP9

JP10

JP9

JP10

JP9

 

1

 

1

 

1

 

1

 

2

 

2

 

2

 

2

 

3

 

3

 

3

 

3

50MHz

55MHz

60MHz

66MHz

CPU External Clock (BUS) Frequency Selection

JP13

JP12

JP13

JP12

JP13

JP12

JP13

JP12

 

1

 

1

 

1

 

1

 

2

 

2

 

2

 

2

 

3

 

3

 

3

 

3

1.5 x

2.0 x

2.5 x

3.0 x

CPU : BUS Frequency Ratio (1.5x, 2.0x, 2.5x, 3.0x)

Set the jumpers by the Internal speed of the Intel, AMD, or Cyrix CPU’s as follows:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(BUS Freq.)

(Freq. Ratio)

 

 

 

 

 

 

CPU Model

Freq.

Ratio

(BUS Freq.)

JP10

JP9

JP13

JP12

Intel Pentium

200MHz

3.0x

66MHz

[2-3]

[1-2]

[2-3]

[1-2]

Intel Pentium

166MHz

2.5x

66MHz

[2-3]

[1-2]

[2-3]

[2-3]

Intel Pentium

150MHz

2.5x

60MHz

[1-2]

[2-3]

[2-3]

[2-3]

Intel Pentium

133MHz

2.0x

66MHz

[2-3]

[1-2]

[1-2]

[2-3]

Intel Pentium

120MHz

2.0x

60MHz

[1-2]

[2-3]

[1-2]

[2-3]

Intel Pentium

100MHz

1.5x

66MHz

[2-3]

[1-2]

[1-2]

[1-2]

Intel Pentium

90MHz

1.5x

60MHz

[1-2]

[2-3]

[1-2]

[1-2]

Intel Pentium

75MHz

1.5x

50MHz

[2-3]

[2-3]

[1-2]

[1-2]

AMD

100MHz

1.5x

66MHz

[2-3]

[1-2]

[1-2]

[1-2]

AMD

90MHz

1.5x

60MHz

[1-2]

[2-3]

[1-2]

[1-2]

AMD

75MHz

1.5x

50MHz

[2-3]

[2-3]

[1-2]

[1-2]

*Cyrix 166+

133MHz

2.0x

66MHz

[2-3]

[1-2]

[1-2]

[2-3]

*The only Cyrix CPU that is supported on this motherboard is labeled Cyrix 6x86 P166+ but must be Revision 2.7 and later. Look on the underside of the CPU for the serial number. The number should read G8DC6620A or larger.

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ASUS P/I-XP55T2P4 User’s Manual