PC3086 DIP switches
The PC3086 has four DIP switches accessible from the back of the case, but only numbers 1 and 2 are used. They control the behaviour of the onboard Paradise graphics chipset.
Switch 1: Monitor type
If this switch is turned on, the graphics modes will be adjusted to give a clearer picture on a multisync monitor. If it is turned off, a fixed- frequency VGA monitor will be assumed.
Switch 2: PS/2 or AT mode
If the switch is on, the video card will automatically switch between colour and monochrome modes depending on what the current program requires. If it is off, then monochrome/colour switching must be done manually with the DISPLAY command.