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).

Function	Jumper	Description
Jfdc (FDC)	1-2 2-3	Enabled Disabled
Jhdc (IDE)	1-2 2-3	Enabled Disabled
Jc13 (COM1/COM3)	1-2 2-3	Proprietary Modem in COM1 Proprietary Modem in COM3
Jc24 (COM2/COM4)	1-2 2-3	Serial Port is COM2 Serial Port is COM4
Jlps (LPT PORT)	1-2 2-3	Select LPT1 Select LPT2
Jlrq (LPT INT)	1-2 2-3	LPT uses IRQ5 LPT uses IRQ7
Jvrq (VGA INT)	IN OUT	Video uses IRQ9 None
Jmrq (MOUSE INT)	IN OUT	Mouse Port uses IRQ12 None
Jvgas (VGA PORT)	1-2 2-3	Built-in VGA Enabled Built-in VGA Disabled
Jgams (GAME PORT)	1-2 2-3	Disabled Enabled
Jvd (DISPLAY)	1-2 2-3	Mono Mode Colour Mode
Jpip (PIPELINE)	IN OUT	Pipelined 80386 Non-pipelined 80386

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).

Total Memory	Dram Bank 0	Dram Bank 1	Simm Bank 2	Simm Bank 3	Extended Memory
1MB	(8)44256	(4)41256	NONE	NONE	384
2MB	(8)44256	(4)41256	(2)256K X 9	(2)256K X 9	1408
3MB	(8)44256	(4)41256	(2) 1MB X 9	NONE	2432
5MB	(8)44256	(4)41256	(2) 1MB X 9	(2) 1MB X 9	4480

Motherboard B - RAM Upgrade

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

Total Memory	Simm Bank 0	Simm Bank 1	Extended Memory
1MB	(2)256K X 9	(2)256K X 9	384
2MB	(2) 1MB X 9	NONE	1408
4MB	(2) 1MB X 9	(2) 1MB X 9	3456
8MB	(2) 4MB X 9	NONE	7552
16MB	(2) 4MB X 9	(2) 4MB X 9	15744