SOYO 5EAS5 P55C - Manual (Page 11)

Hardware Setup 7
JP16: PCI Bus Asynchronous/Synchronous Jumper
Asynchronous and synchronous (default) PCI bus frequency settings are
available.
PCI Bus Setting JP16
Asychronous
1
Synchronous
1
Divides the host bus by 2 to get the Asynchronous setting, and sets the
PCI bus on 32MHz to get the synchronous setting. Set JP16 to
Synchronous mode when the system is unstable.
Host Bus
(CPU Bus)
PCI Bus Frequency
(Synchronous)
PCI Bus Frequency
(Asynchronous)
50 MHz* 25 MHz 32 MHz
55 MHz* 27.5 MHz 32 MHz
60 MHz 30 MHz 32 MHz
66 MHz 33.3 MHz 32 MHz
75 MHz** 37.5 MHz 32 MHz
*: Do not use Asynchronous setting when the host bus frequency is
50MHz or 55MHz.
**: Do not use Synchronous setting when the host bus frequency is 75
MHz.