Apollo IV PCI Pentium ISA Motherboard User’s Guide
14
Step 3 Configure CPU
Important
Perform the following steps to configure the
motherboard before installing a CPU.
External CPU Clock CLK1, CLK2, and CLK3 are 3-pin bergs that set the CPU external clock
frequency. This motherboard may have any of four different clock generators:
•
IMI652,
•
ICS 9147,
•
ICW, or
•
PhaseLink.
The CLK1, CLK2, and CLK3 settings are different with the different clock
generators. You must determine the clock generator type (it’s next to the
CPU) before setting these jumpers.
IMI 652 Clock Generator The following CLK1, CLK2, and CLK3 settings apply only if an
IMI 652 clock generator is mounted on the motherboard.
External
(CPUCLK)
CLK1
CLK2
FREQ1
66 MHz
Short Pins 1-2
Short Pins 1-2
Short Pins 2-3
60 MHz
Short Pins 2-3
Short Pins 1-2
Short Pins 2-3
55 MHz
Short Pins 2-3
Short Pins 2-3
Short Pins 2-3
50 MHz
N/A
N/A
N/A
Cont’d
