80386SX-20/25 SC/SI Motherboard Settings and Configuration

Processor	80386SX
Processor Speed	20/25MHz
Chip Set	Symphony
Max. Onboard DRAM	32MB
Cache	16/32/64/128KB
BIOS	AMI
Dimensions	330mm x 218mm
I/O Options	None
NPU Options	80387SX

CONNECTIONS
Purpose	Location	Purpose	Location
Turbo switch	JP30	Speaker	JP33
Turbo LED	JP31	Power LED & keylock	JP34
Reset switch	JP32

USER CONFIGURABLE SETTINGS
Function		Jumper	Position
»	Monitor type select monochrome/EGA	JP2	Open
	Monitor type select color	JP2	Closed
Note:JP21 is also used to set cache size, therefore its setting will vary when cache is enabled.

DRAM CONFIGURATION
Size	Bank 0	Bank 1	Bank 2	Bank 3
512KB	(2) 256K x 9	NONE	NONE	NONE
1MB	(2) 256K x 9	(2) 256K x 9	NONE	NONE
1.5MB	(2) 256K x 9	(2) 256K x 9	(2) 256K x 9	NONE
2MB	(2) 256K x 9	(2) 256K x 9	(2) 256K x 9	(2) 256K x 9
2MB	(2) 1M x 9	NONE	NONE	NONE
2.5MB	(2) 256K x 9	(2) 1M x 9	NONE	NONE
3MB	(2) 256K x 9	(2) 256K x 9	(2) 1M x 9	NONE
4MB	(2) 1M x 9	(2) 1M x 9	NONE	NONE
5MB	(2) 256K x 9	(2) 256K x 9	(2) 1M x 9	(2) 1M x 9
6MB	(2) 1M x 9	(2) 1M x 9	(2) 1M x 9	NONE
8MB	(2) 1M x 9	(2) 1M x 9	(2) 1M x 9	(2) 1M x 9
8MB	(2) 4M x 9	NONE	NONE	NONE
9MB	(2) 256K x 9	(2) 256K x 9	(2) 4M x 9	NONE
10MB	(2) 1M x 9	(2) 4M x 9	NONE	NONE
12MB	(2) 1M x 9	(2) 1M x 9	(2) 4M x 9	NONE
16MB	(2) 4M x 9	(2) 4M x 9	NONE	NONE
18MB	(2) 1M x 9	(2) 4M x 9	(2) 4M x 9	NONE
20MB	(2) 1M x 9	(2) 1M x 9	(2) 4M x 9	(2) 4M x 9
24MB	(2) 4M x 9	(2) 4M x 9	(2) 4M x 9	NONE
26MB	(2) 1M x 9	(2) 4M x 9	(2) 4M x 9	(2) 4M x 9
32MB	(2) 4M x 9	(2) 4M x 9	(2) 4M x 9	(2) 4M x 9

CACHE CONFIGURATION
Size	Bank 0	Bank 1	TAG
16KB	(2) 8K x 8	NONE	(1) 8K x 8
32KB	(2) 8K x 8	(2) 8K x 8	(1) 8K x 8
64KB	(2) 32K x 8	NONE	(1) 32K x 8
128KB	(2) 32K x 8	(2) 32K x 8	(1) 32K x 8

CACHE JUMPER CONFIGURATION
Size	JP3	JP10	JP16	JP17	JP18	JP19	JP20	JP21	JP27	JP29
16KB	1 & 2	1 & 2	1 & 2	Open	1 & 2	1 & 2	1 & 2	1 & 2	Open	Closed
32KB	1 & 2	1 & 2	1 & 2	1 & 2	2 & 3	2 & 3	2 & 3	2 & 3	Closed	Open
64KB	2 & 3	2 & 3	1 & 2	Open	2 & 3	1 & 2	1 & 2	1 & 2	Open	Closed
128KB	2 & 3	2 & 3	2 & 3	2 & 3	2 & 3	2 & 3	2 & 3	2 & 3	Closed	Open
Note:Pins designated should be in the closed position.

CACHE JUMPER CONFIGURATION
Setting	JP4	JP5	JP6	JP7	JP8
Enabled	1 & 2	1 & 2	Open	Open	Open
Disabled	2 & 3	2 & 3	Closed	Closed	Closed
Note:Pins designated should be in the closed position.

CACHE JUMPER CONFIGURATION (CON’T)
Setting	JP9	JP11	JP12	JP13	JP14	JP15
Enabled	Open	Open	Open	1 & 2	Open	Open
Disabled	Closed	Closed	Closed	Open	Closed	Closed
Note:Pins designated should be in the closed position.

CACHE JUMPER CONFIGURATION (CON’T)
Setting	JP22	JP23	JP24	JP25	JP26	JP28
Enabled	Open	Open	Closed	Open	Open	Open
Disabled	Closed	Open	Open	Closed	Closed	Closed