38
2.
From the table below, and the label on your upgrade
processor or its packaging, decide which processor
type you have installed.
Since the Intel487SX and OverDrive upgrade
processors require the same configuration you will
normally set switches 4 and 5 to the Off/Off position.
The other selections are for processors normally
installed during manufacture.
Switch
Processor
4
5
off
off
Intel487SX/OverDrive Upgrade
off
on
Intel486DX/Intel486DX2/
OverDrive Replacement
on
off
Intel486SX
on
on
not used
3.
Having decided which selection you require check
the positions of switches 4 and 5, and if necessary
move them to the appropriate position.
The easiest way to move the switches is with the
point of a pencil or small screwdriver.
4.
From the table below, and the label on your upgrade
processor, or its packaging decide which system
clock speed you need to select.
Switch
Clock speed
2
3
(MHz)
on
on
16
on
off
20
off
on
25
off
off
33
You will almost certainly want to set the clock speed
to either 25 or 33MHz.
If you have installed an Intel487SX you must set the
system clock speed to match the speed of the
coprocessor.