Acorp 5VIA73 Manual page 20

JP1 CPU Ratio Selection (6-8)
This Jumpter 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 Jumpter
CPU model ratio bus frequency.
JP1 CPU Ratio Selection (6-8)
CPU Ratio
20 / Chapter 3 Installation
15-16 13-14
OFF ON
OFF ON
OFF OFF
OFF OFF
ON ON
ON ON
ON OFF
ON OFF
11-12 Ratio
ON 2.5
OFF 3.0
ON 2.0
OFF 1.5/3.5
ON 4.5
OFF 5.0
ON 4.0
OFF 5.5