Table Of Contents; Core/Bus Ratio; On Off On; On On Off - MSI LPX ZX4 User Manual

2.1-1 CPU Core Speed Derivation Procedure

1. The DIP Switch SW1 (1, 2, 3, and 4) is used to set the Core/Bus (Fraction)
ratio of the CPU. The actual core speed of the CPU is the Host Clock
Frequency multiplied by the Core/Bus ratio. For example:
If
then
1
ON
ON
ON
ON
ON
ON
ON
OFF
OFF
OFF
OFF
OFF
CPU Clock
Core/Bus ratio
CPU core speed
2 3
OFF ON
ON OFF
OFF OFF
ON ON
OFF ON
ON OFF
OFF OFF
ON ON
OFF ON
ON OFF
OFF OFF
ON ON
= 66MHz
= 5.5
= Host Clock x Core/Bus ratio
= 66MHz x 5.5
= 333 MHz
4

Core/Bus Ratio

ON
ON
ON
OFF
OFF
OFF
OFF
ON
ON
ON
ON
OFF
2-2
2.5
3
3.5
4
4.5
5
5.5
6
6.5
7
7.5
8