486 US Motherboard Settings and Configuration

Processor	80486SX/80487SX/80486DX
Processor Speed	20/25/33/50MHz
Chip Set	UMC
Max. Onboard DRAM	32MB
Cache	64/128/256KB
BIOS	AMI/Phoenix
Dimensions	330mm x 218mm
I/O Options	32-bit external memory card slot
NPU Options	4167

CONNECTIONS
Purpose	Location	Purpose	Location
External battery	J1	Turbo switch	J6
Power LED & keylock	J3	Turbo LED	J7
Speaker	J4	32-bit external memory card	S1
Reset switch	J5

USER CONFIGURABLE SETTINGS
Function		Jumper	Position
»	Monitor type select color	JP10	Open
	Monitor type select monochrome	JP10	Closed
»	Bus speed select fast	JP12	pins 1 & 2 closed
	Bus speed select slow	JP12	pins 2 & 3 closed
»	CMOS memory normal operation	JP19	Open
	CMOS memory clear	JP19	Closed

DRAM CONFIGURATION
Size	Bank 0	Bank 1	Bank 2	Bank 3
1MB	(4) 256K x 9	NONE	NONE	NONE
2MB	(4) 256K x 9	(4) 256K x 9	NONE	NONE
3MB	(4) 256K x 9	(4) 256K x 9	(4) 256K x 9	NONE
4MB	(4) 256K x 9	(4) 256K x 9	(4) 256K x 9	(4) 256K x 9
4MB	(4) 1M x 9	NONE	NONE	NONE
5MB	(4) 256K x 9	(4) 1M x 9	NONE	NONE
6MB	(4) 256K x 9	(4) 256K x 9	(4) 1M x 9	NONE
7MB	(4) 256K x 9	(4) 256K x 9	(4) 256K x 9	(4) 1M x 9
8MB	(4) 1M x 9	(4) 1M x 9	NONE	NONE
9MB	(4) 256K x 9	(4) 1M x 9	(4) 1M x 9	NONE
10MB	(4) 256K x 9	(4) 256K x 9	(4) 1M x 9	(4) 1M x 9
12MB	(4) 1M x 9	(4) 1M x 9	(4) 1M x 9	NONE
16MB	(4) 1M x 9	(4) 1M x 9	(4) 1M x 9	(4) 1M x 9
16MB	(4) 4M x 9	NONE	NONE	NONE
17MB	(4) 256K x 9	(4) 4M x 9	NONE	NONE
18MB	(4) 256K x 9	(4) 256K x 9	(4) 4M x 9	NONE
20MB	(4) 1M x 9	(4) 4M x 9	NONE	NONE
24MB	(4) 1M x 9	(4) 1M x 9	(4) 4M x 9	NONE
28MB	(4) 1M x 9	(4) 1M x 9	(4) 1M x 9	(4) 4M x 9
32MB	(4) 4M x 9	(4) 4M x 9	NONE	NONE
36MB	(4) 1M x 9	(4) 4M x 9	(4) 4M x 9	NONE
40MB	(4) 1M x 9	(4) 1M x 9	(4) 4M x 9	(4) 4M x 9
48MB	(4) 4M x 9	(4) 4M x 9	(4) 4M x 9	NONE
52MB	(4) 1M x 9	(4) 4M x 9	(4) 4M x 9	(4) 4M x 9
64MB	(4) 4M x 9	(4) 4M x 9	(4) 4M x 9	(4) 4M x 9
Note:Banks 2 & 3 are used when a 32-bit external memory card is installed at S1.

CACHE CONFIGURATION
Size	Bank 0	Bank 1
64KB	(4) 8K x 8	(4) 8K x 8
128KB	(4) 32K x 8	NONE
256KB	(4) 32K x 8	(4) 32K x 8

CACHE CONFIGURATION
Size	JP13	JP14	JP16	JP17	JP18
64KB	1 & 2	1 & 2	2 & 3	1 & 2	1 & 2
128KB	2 & 3	1 & 2	2 & 3	2 & 3	1 & 2
256KB	1 & 2	2 & 3	2 & 3	2 & 3	2 & 3
Note:Pins designated should be in the closed position.

CPU TYPE CONFIGURATION
Type	JP1	JP2	JP3	JP8
80486SX	Open	pins 2 & 3 closed	pins 3 & 4 closed	Closed
80487SX	Closed	pins 1 & 2 closed	pins 2 & 3 closed	Closed
80486DX	Closed	pins 1 & 2 closed	pins 1 & 2 closed	Open