Packard Bell 300/320 M/Board

Specification

This motherboard's built-in video card does not have a 132-column mode as stated in the manual. Systems with "PB320" on the back stickers are 20MHz PB300 series computers.

• Battery : 3.6V DC NiCad soldered on motherboard
• BIOS :
  • 2 X 64K Phoenix BIOS Chip at U40: Phoenix 1.10.1110
  • No chip at U40: Phoenix 1.10.1111
  • No chip at U40 and ACC micro chip with SC01 at the end: Phoenix 1.10.1114
  • To access Setup : Ctrl-Alt-S
• Bus Architecture : ISA based system bus
• Cache : N/A
• CPU : 80386SX-16 MHz, 80386SX-20 MHz. Keyboard Switchable (Ctrl)-(Alt)-(-) = 8 MHz, (Ctrl)-(Alt)-(+) = 16/20 MHz.
• Interfaces :
  • 1 DB-25 Parallel Port
  • 1 DB-9 Serial ports
  • 1 15 pin VGA port
  • 1 Proprietary modem connector
  • 1 15 pin game port
  • 1 PS/2 Keyboard port
  • 1 PS/2 Mouse port
• RAM : 1MB standard, Maximum on Motherboard 16 MB
• Speaker : Piezoelectric, soldered on motherboard
• Video : Paradise built into motherboard
• Video RAM : 256K

Jumpers

Notes -

When replacing the motherboard and installing or removing a modem, ensure that the JMOD connector is configured properly.

There are about 100 motherboards, similar to Motherboard A, that have 8 SIMM sockets; only four are enabled.

There are three revisions to this motherboard.

• Motherboard A - has 1MB surface mount DRAMs upgradable to 5MB.
• Motherboard B -
  • Does not have surface mount DRAMs upgradable to 16MB.
  • There are 4 sets of traces for SIMM sockets in front of bank 0 and bank 1 labelled sim5,sim6,sim7 and sim8. Additional SIMM sockets cannot be installed.
  • U40 is only present on 20MHz system.
• Motherboard C -
  • Has 2MB surface mount DRAMs; CPU is 16, 20 or 25MHz.
  • A 301-252 (256K video memory) on-board video disabled and a 512K OAK video card.
  • A 301-V252 has 512K of video memory in addition to a 25 MHz CPU.

Some computers have the game port jumpers reversed (1-2 Enabled 2-3 Disabled).

JLPS, JC24, JHDC, JFDC and JC13 will be obstructed by the internal modem connected to JMOD (if installed).

Upgrades

• Battery : 3.6V DC NiCad soldered onto motherboard.
• Maths Co-Processor : An 80387SX Co-processor can be installed in socket U41, no jumpers need to be changed. Co-processor speed must match system speed.
• RAM :
  • When upgrading any one of these systems, use SIMMs that have 9 chips on them rather then the ones with 3 chips.
  • There are 2 variations of motherboard for this system, each one with different memory configuration, see tables below.
  • SHADOW BIOS and SHADOW VIDEO take 128k off Extended Memory if either or both enabled.
  • No Jumper setting required.
  • Recommended SIMM speed is 80 ns.

Motherboard A - RAM Upgrade

System with surface mount DRAMs (44256s and 41256s) totaling 1MB, and 4 SIMM sockets. (Supports 256Kb and 1MB SIMMs only).

Motherboard B - RAM Upgrade

System with NO surface mount DRAMs, and 4 SIMM sockets. (Supports 256Kb, 1MB and 4MB SIMMs).