ASUS P/I-P55TVP4 User's Manual10
III. INSTALLATION
(Jumpers)
III. INSTALLATION
6. CPU External (BUS) Frequency Selection (JP1, JP2, JP3)
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 times the BUS Ratio equals the CPU's Internal frequency (the advertised
CPU speed).
7. CPU to BUS Frequency Ratio (JP5, JP6)
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.
50MHz 55MHz 60MHz 66MHz
CPU External Clock (BUS) Frequency Selection
JP2
1
2
3
JP1
JP3
JP2
1
2
3
JP1
JP3
JP2
1
2
3
JP1
JP3
JP2
1
2
3
JP1
JP3
CPU : BUS Frequency Ratio (1.5x, 2.0x, 2.5x, 3.0x)
1.5 x
JP6
JP5
2.0 x
JP6
JP5
2.5 x
JP6
JP5
3.0 x
JP6
JP5
Set the jumpers by the Internal speed of the Intel, AMD, or Cyrix CPU as follows:
(BUS Freq.) (Freq. Ratio)
CPU Model Freq. Ratio BUS Freq. JP3 JP2 JP1 JP6 JP5
Intel Pentium 200MHz 3.0x 66MHz [1-2] [1-2] [1-2] [1-2] [2-3]
Intel Pentium 180MHz 3.0x 60MHz [1-2] [2-3] [1-2] [1-2] [2-3]
Intel Pentium 166MHz 2.5x 66MHz [1-2] [1-2] [1-2] [2-3] [2-3]
Intel Pentium 150MHz 2.5x 60MHz [1-2] [2-3] [1-2] [2-3] [2-3]
Intel Pentium 133MHz 2.0x 66MHz [1-2] [1-2] [1-2] [2-3] [1-2]
Intel Pentium 120MHz 2.0x 60MHz [1-2] [2-3] [1-2] [2-3] [1-2]
Intel Pentium 100MHz 1.5x 66MHz [1-2] [1-2] [1-2] [1-2] [1-2]
Intel Pentium 90MHz 1.5x 60MHz [1-2] [2-3] [1-2] [1-2] [1-2]
Intel Pentium 75MHz 1.5x 50MHz [2-3] [2-3] [1-2] [1-2] [1-2]
AMD 100MHz 1.5x 66MHz [1-2] [1-2] [1-2] [1-2] [1-2]
AMD 90MHz 1.5x 60MHz [1-2] [2-3] [1-2] [1-2] [1-2]
AMD 75MHz 1.5x 50MHz [2-3] [2-3] [1-2] [1-2] [1-2]
*Cyrix 166+ 133MHz 2.0x 66MHz [1-2] [1-2] [1-2] [2-3] [1-2]
*NOTE: Only Cyrix Revision 2.7 or later is supported on this motherboard. See page 9 for revision
identification. Bootup screen will show 6x86-P166+ -S CPU at 133MHz with the Cyrix
166+ installed on this motherboard.