ASUS C-P55T2D User’s Manual 3
III. INSTALLATION
Jumper Settings
CPU to BUS Frequency Ratio (JP15, 16)
These jumpers set the frequency ratio between the Internal frequency of the
CPU and the External frequency (called the BUS Clock) within the CPU.
CPU : BUS Frequency Ratio
Complete Names:
Intel Pentium P54C, P55C-MMX
AMD K5, K6
IBM/Cyrix 6X86, 6x86MX
P54C/K5
P55C/K6/MX
IBM/Cyrix 6X86
3.0x(3/1)
3.0x(3/1)
4.0x(4/1)
2.5x(5/2)
2.5x(5/2)
1.0x(1/1)
2.0x(2/1)
2.0x(2/1)
2.0x(2/1)
1.5x(3/2)
3.5X(7/2)
3.0x(3/1)
1
2
JP15
JP16
3/2 2 5/2 3
Set the jumpers by the Internal speed of the Intel Pentium or compatible CPUs as follows:
(CPU Card (CPU Ext. Freq
CPU BUS BUS Ratio) Ext. on Baseboard)
Internal Ratio JP15 JP16 Freq. JP3 JP2
233MHz 3.5x [OFF] [OFF] 66MHz [1-2] [2-3]
200MHz 3.0x [ON] [OFF] 66MHz [1-2] [2-3]
166MHz 2.5x [ON] [ON] 66MHz [1-2] [2-3]
150MHz 2.5x [ON] [ON] 60MHz [2-3] [1-2]
133MHz 2.0x [OFF] [ON] 66MHz [1-2] [2-3]
120MHz 2.0x [OFF] [ON] 60MHz [2-3] [1-2]
100MHz 1.5x [OFF] [OFF] 66MHz [1-2] [2-3]
90MHz 1.5x [OFF] [OFF] 60MHz [2-3] [1-2]
75MHz 1.5x [OFF] [OFF] 50MHz [1-2] [1-2]
CPU External Clock (BUS) Frequency Selection
60MHz
JP2
JP3
1
2
3
66MHz
JP2
JP3
1
2
3
50MHz
JP2
JP3
1
2
3
III. INSTALLATION
(Jumpers)
WARNING: The CPU and/or motherboard will overheat if there is no
airflow across the CPU and onboard heatsinks.