Chapter 1 Hardware Installation
15
Step 3 Configure CPU,
Continued
ICS 9147 Clock Generator The following CLK1, CLK2, and CLK3 settings apply only if an
ICS 9147 clock generator is mounted on the motherboard.
External
(CPUCLK)
CLK1
CLK2
FREQ1
66 6 MHz
Short Pins 1-2
Short Pins 2-3
Short Pins 2-3
60 MHz
Short Pins 2-3
Short Pins 2-3
Short Pins 2-3
55 MHz
Short Pins 1-2
Short Pins 1-2
Short Pins 2-3
50 MHz
Short Pins 2-3
Short Pins 1-2
Short Pins 2-3
ICW or PhaseLink Clock Generator The following CLK1, CLK2, and CLK3 settings apply
only if an ICW or PhaseLink clock generator is mounted on the motherboard.
External
(CPUCLK)
CLK1
CLK2
FREQ1
66 6 MHz
Short Pins 1-2
Short Pins 1-2
Short Pins 1-2
60 MHz
Short Pins 2-3
Short Pins 1-2
Short Pins 1-2
55 MHz
Short Pins 2-3
Short Pins 2-3
Short Pins 1-2
50 MHz
N/A
N/A
N/A
CPU/Bus Frequency Ratio FREQ1, FREQ2, and FREQ3 are 3-pin bergs that set the ratio of
the internal CPU frequency to the bus clock.
For
P54C
For
P55C,
and K6
For
K5
FREQ1
FREQ2
FREQ3
3x
3x
2x
Short Pins 1-2
Short Pins 2-3
Short Pins 1-2
2.5x
2.5x
1.75x
Short Pins 2-3
Short Pins 2-3
Short Pins 1-2
2x
2x
N/A
Short Pins 2-3
Short Pins 1-2
Short Pins 1-2
1.5x
3.5x
1.5x
Short Pins 1-2
Short Pins 1-2
Short Pins 1-2
Cont’d