MB-486 DX-33 UM Motherboard Settings and Configuration

Processor	80486SX/80487SX/80486DX
Processor Speed	33MHz
Chip Set	UMC
Max. Onboard DRAM	40MB
Cache	64/128/256KB
BIOS	AMI
Dimensions	330mm x 218mm
I/O Options	None
NPU Options	4167

CONNECTIONS
Purpose	Location	Purpose	Location
Power LED & keylock	J1	Reset switch	J4
Speaker	J2	Turbo LED	J5
Turbo switch	J3	External battery	J6

USER CONFIGURABLE SETTINGS
Function		Jumper	Position
»	Monitor type select CGA	W18	Closed
	Monitor type select monochrome/EGA/VGA	W18	Open
»	Battery select internal	W22	Closed
	Battery select external	W22	Open

DRAM CONFIGURATION
Size	Bank 0	Bank 1	Bank 2	Bank 3
1MB 1	(4) 256K x 9	NONE	NONE	NONE
1MB 2	NONE	NONE	(1) 256K x 36	NONE
2MB 1	(4) 256K x 9	(4) 256K x 9	NONE	NONE
2MB 2	NONE	NONE	(1) 256K x 36	(1) 256K x 36
3MB 1	(4) 256K x 9	(4) 256K x 9	(1) 256K x 36	NONE
3MB 2	(4) 256K x 9	NONE	(1) 256K x 36	(1) 256K x 36
4MB 1	(4) 256K x 9	(4) 256K x 9	(1) 256K x 36	(1) 256K x 36
4MB 2	(4) 256K x 9	(4) 256K x 9	(1) 256K x 36	(1) 256K x 36
4MB 1	(4) 1M x 9	NONE	NONE	NONE
4MB 2	NONE	NONE	(1) 1M x 36	NONE
5MB 1	(4) 256K x 9	(4) 1M x 9	NONE	NONE
5MB 2	NONE	NONE	(1) 256K x 36	(1) 1M x 36
6MB 1	(4) 256K x 9	(4) 256K x 9	(1) 1M x 36	NONE
6MB 2	(4) 1M x 9	NONE	(1) 256K x 36	(1) 256K x 36
8MB 1	(4) 1M x 9	(4) 1M x 9	NONE	NONE
8MB 2	NONE	NONE	(1) 1M x 36	(1) 1M x 36
9MB 1	(4) 256K x 9	(4) 1M x 9	(1) 1M x 36	NONE
9MB 2	(4) 1M x 9	NONE	(1) 256K x 36	(1) 1M x 36
10MB 1	(4) 256K x 9	(4) 256K x 9	(1) 1M x 36	(1) 1M x 36
10MB 2	(4) 1M x 9	(4) 1M x 9	(1) 256K x 36	(1) 256K x 36
12MB 1	(4) 1M x 9	(4) 1M x 9	(1) 1M x 36	NONE
12MB 2	(4) 1M x 9	NONE	(1) 1M x 36	(1) 1M x 36
16MB 1	(4) 1M x 9	(4) 1M x 9	(1) 1M x 36	(1) 1M x 36
16MB 2	(4) 1M x 9	(4) 1M x 9	(1) 1M x 36	(1) 1M x 36
16MB 1	(4) 4M x 9	NONE	NONE	NONE
16MB 2	NONE	NONE	(1) 4M x 36	NONE
20MB 1	(4) 1M x 9	(4) 4M x 9	NONE	NONE
20MB 2	NONE	NONE	(1) 1M x 36	(1) 4M x 36
24MB 1	(4) 1M x 9	(4) 1M x 9	(1) 4M x 36	NONE
24MB 2	(4) 4M x 9	NONE	(1) 1M x 36	(1) 1M x 36
32MB 1	(4) 4M x 9	(4) 4M x 9	NONE	NONE
32MB 2	NONE	NONE	(1) 4M x 36	(1) 4M x 36
40MB 1	(4) 1M x 9	(4) 1M x 9	(1) 4M x 36	(1) 4M x 36
40MB 2	(4) 4M x 9	(4) 4M x 9	(1) 1M x 36	(1) 1M x 36
Note 1 :On jumpers W12, W13, W15, and W16 - pins 1 & 2 should be in the closed position. Note 2 :On jumpers W12, W13, W15, and W16 - pins 2 & 3 should be in the closed position.

CACHE CONFIGURATION
Size	Bank 0	Bank 1	Dirty Bit (U10)	TAG (U11)
64KB	(4) 8K x 8	(4) 8K x 8	(1) 16K x 8	(1) 8K x 8
128KB	(4) 32K x 8	NONE	(1) 16K x 8	(1) 8K x 8
256KB	(4) 32K x 8	(4) 32K x 8	(1) 16K x 8	(1) 32K x 8

CACHE JUMPER CONFIGURATION
Size	W2	W3	W4	W5	W6	W7	W8	W9
64KB	1 & 2	1 & 2	Open	1 & 2	Open	Open	Open	Open
128KB	2 & 3	1 & 2	1 & 2	2 & 3	Closed	Open	Open	Open
256KB	2 & 3	2 & 3	2 & 3	1 & 2	Closed	Closed	Closed	Closed
Note: Pins designated should be in the closed position.

CPU TYPE CONFIGURATION
Type	W10	W11
80486SX	Open	pins 2 & 3 closed
80487SX	pins 2 & 3 closed	pins 1 & 2 and 3 & 4 closed
80486DX	pins 1 & 2 closed	pins 1 & 2 and 3 & 4 closed