Packard Bell 800/900 M/Board

There are two revisions of the PB800/900 motherboard.

Revision C

800a board diagram

NOTE: Holds 1MB of RAM (256 x 1 chips), arranged in four rows of nine chips per row (8 bits of RAM and 1 parity bit.) The CMOS backup battery is a removable AT style battery.

Revision D

800b board diagram

Holds 1MB of RAM (256K x 4 chips) arranged in 2 rows of 4 and parity 1 row of 4 (256K x 1 chips) upgradeable to 2MB with same chips plugged in adjacent sockets. CMOS Battery is soldered.

Specification

2 motherboard revisions: Rev.C requires matching BIOS and Chips chipsets. Supports 1MB. Rev.D supports 2MB on motherboard. There is no difference between the PB800 and the PB900.

Jumpers

JumperFunctionPinsDescription
J1980287 Clock Speed1-2
3-4
80287-8
80287-10
COLOUR/MONODisplay Mode1-2
2-3
Colour
Monochrome

Upgrades