DC-486SX 25/33/50 Motherboard Settings and Configuration

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

CONNECTIONS
Purpose	Location	Purpose	Location
External battery	J10	32-bit external memory card	S1
Power LED & keylock	J23	Reset switch	SW1
Speaker	J24	Turbo switch	SW2
Turbo LED	JP12

USER CONFIGURABLE SETTINGS
Function		Jumper	Position
»	Monitor type select color	JP1	Closed
	Monitor type select monochrome	JP1	Open
»	CMOS memory normal operation	JP2	pins 2 & 3 closed
	CMOS memory clear	JP2	pins 1 & 2 closed
»	Bus speed select ATCLK/6	JP3	Closed
	Bus speed select ATCLK/4	JP3	Open
»	CPU speed select OSC/2	JP4	pins 2 & 3 closed
	CPU speed select OSC/1	JP4	pins 1 & 2 closed

DRAM CONFIGURATION
Size	Bank 0	Bank 1	Bank 2	Bank 3
4MB	(4) 1M x 9	NONE	NONE	NONE
8MB	(4) 1M x 9	(4) 1M x 9	NONE	NONE
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
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
64KB	(9) 8K x 8
256KB	(9) 32K x 8

CACHE JUMPER CONFIGURATION
Size	JP8	JP9	JP10	JP11
64KB	Open	Open	Open	Open
256KB	Closed	Closed	Closed	Closed

CPU TYPE CONFIGURATION
Type	JP5	JP6	JP7
80486SX	Open	pins 2 & 3 closed	Closed
80487SX	pins 1 & 2 closed	pins 1 & 2 closed	Closed
80486DX	pins 2 & 3 closed	pins 1 & 2 closed	Closed