Packard Bell 450 M/Board

450 board diagram

Specification

Battery : 3.0V DC Lithium soldered on motherboard.
BIOS : Phoenix v4.03 X1.1A
Bus Architecture : ISA based system bus.
Cache : Write Back: 8 KB Internal (Level 1) Cache External (Level 2).
CPU : Intel 486 processor.
Interfaces :
- 1 DB-25F Parallel.
- 1 RS232,DB-9M Serial.
- 1 15-pin HDF VGA.
- 1 PS/2 Mouse.
- 1 PS/2 Keyboard.
RAM : 4 MB Standard on Motherboard 64 MB Maximum on Motherboard.
Speaker : Piezoelectric soldered on motherboard.
UART : Compatability Compatible with the 16C550 UART.
Video : Built in Cirrus Logic 5428 or 5429.

Jumpers

Jumper	Function	Setting	Description
J8	Color/Mono select	Closed Open	* Colour Monochrome
J9	Video IRQ enable	Closed Open	* Enabled Disabled
J10	Password clear	Closed Open	Clear Password * Normal Operation
J11	Onboard game port select	Closed Open	* Enabled Disabled
** J15 / J16	ECP DMA select	1-2 2-3	* DMA Channel 1 DMA Channel 2
J17	Boot Select	1-2 2-3	Boot Block * Normal
J18	Parity Enable	1-2 2-3	Enabled * Disabled
J19	Onboard VGA Enable	1-2 2-3	Disabled * Enabled
J20	Onboard I/O Controller	1-2 2-3	Disabled * Enabled
J25	CPU Speed select	1-2 2-3	25MHz 33MHz
J26	Cache size selection	Open 1-2, 3-4	0K 128K 512K
J28	P24T or S-series reset control	1-2 2-3	* P24T S-series CPU Standard CPU (Do Not Change to add P24)
J29	P24C Clock multiplier	1-2 2-3 Open	Other Multiplier X2 Internal clock X3 Internal clock
J30	Onboard battery enable	Open 3-4	Use external battery * Use internal battery
J31	SX processor selection	1-2 3-4 5-6	All except (SX) SX
J32	J(3.3v) (CPU voltage)	1-3 2-4 3-5 4-6	3.3V CPU * 5.0V CPU
J33	LDEV bypass	Open Closed	Disabled Enabled
J36	Onboard speaker enable	Open 3-4	External speaker * Internal speaker
J37	Onboard memory Disable	Open Closed	* Enabled Disabled

* Indicates default value.
** J15 and J16 must match

Battery

Use a 3 volt lithium battery. Remove the jumpers on pins 3-4 of the J30 (Jbte) battery connector. The battery will connect to pins 1 and 4 (pin 1= +3 volts, pin 4= ground)

Cache Upgrade

The Cache and TAG RAM are either 28-pin for 128KB of cache, or 32-pin for 512KB of cache.

	J26
None	Open
128k	Open
512k	Closed

CPU Upgrades

Jumpers	J25	J29	J31
CPU	Speed	Multiplier	SX/DX
486SX25	1-2	1-2	5-6
486SX33	2-3	1-2	5-6
486SX/2-50	1-2	2-3	5-6
486DX-33	2-3	1-2	1-2 & 3-4
486DX/2-50 486-25 486DX/4-75 P24T-62MHz	1-2	2-3	1-2 & 3-4
486DX/2-66 ODP486-33 P24T-83MHz	2-3	2-3	1-2 & 3-4
486DX/4-100	2-3	none	1-2 & 3-4

The motherboard DOES NOT support any 3.3 Volt CPU?s, regardless of motherboard revision.
The upgrade processor installs in the Zero Insertion Force (ZIF) socket at location U50.
Jumper J29 is not available on all systems.
If you wish to upgrade the processor with an Intel P24T (Pentium Overdrive), the Interposer is required. An Interposer can be obtained from Intel or from the dealer. Please note that the Interposer will disable the 2nd level cache.
For the P24T-83, you may also need to update the BIOS to version 1.1a. The current BIOS version appears on the display immediately after starting up.

Memory Upgrades

This motherboard does not accept EDO memory.
SIMM speed must be 70 or 80ns. 60ns SIMMS will only work if the on-board memory is disabled.
The SIMMS are 72-pin, non-parity (32 bit) because the motherboard design does not require parity checking. The parity jumper does not have to be changed.
Use silver plated SIMMS.
The board comes with 4MB soldered onto the motherboard (SMT), and will take 4/8/16/32 MB SIMMs up to a maximum of 64MB.
When two 32 MB SIMMS are installed, the SMT memory needs to be disabled. This is done by jumping J37 (On Board Memory Disable).

Speaker

Use an 8 ohm, .5 watt computer speaker. Remove the jumper on pins 3-4 of the J36 (Jspk) connector. The Speaker will connect to pins 1 and 4. (pin 1= =5 volts, pin 4=speaker ground).

Video Memory Upgrade

You can upgrade the video memory on your system from 1MB to 2MB by using 256Kx16 (Symmetrical, CAS line) DRAM ZIP?s.
You will need two of these to perform the upgrade.