Processor	80486SX/80486DX/80486DX2
Processor Speed	20/25/33/40/50(internal)/50/66(internal)MHz
Chip Set	OPTI
Max. Onboard DRAM	32MB
Cache	64/128/256/512KB
BIOS	AMI
Dimensions	330mm x 218mm
I/O Options	None
NPU Options	4167

CONNECTIONS
Purpose	Location	Purpose	Location
Speaker	J4	Reset switch	J9
Power LED & keylock	J5

USER CONFIGURABLE SETTINGS
Function		Jumper	Position
»	I/O bus speed select normal	JP1	Open
	I/O bus speed select slow	JP1	Closed
»	Monitor type select monochrome	JP5	Open
	Monitor type select color	JP5	Closed
»	Burst mode enabled	JP7	Closed
	Burst mode disabled	JP7	Open

DRAM CONFIGURATION
Size	Bank 0	Bank 1
4MB	(4) 1M x 9	NONE
8MB	(4) 1M x 9	(4) 1M x 9
16MB	(4) 4M x 9	NONE
20MB	(4) 1M x 9	(4) 4M x 9
32MB	(4) 4M x 9	(4) 4M x 9

CACHE CONFIGURATION
Size	Bank 0	Bank 1	TAG (U52)	TAG (U52)	Dirty Bit(U66)
64KB	4) 8K x 8	4) 8K x 8	(1) 8K x 8	N/A	(1) 16K x 1
128KB	(4) 32K x 8	NONE	(1) 8K x 8	N/A	(1) 16K x 1
256KB	(4) 32K x 8	(4) 32K x 8	(1) 8K x 8	(1) 8K x 8	(1) 16K x 1
512KB	(4) 128K x 8	NONE	(1) 32K x 8	N/A	(1) 64K x 1
Note:You may use a (1) 64K x 1 at U66 for all Cache SRAM sizes .

CACHE JUMPER CONFIGURATION
Size	JP6	JP11	JP12	JP13	JP14	JP15	JP16
64KB	2 & 3	Open	Open	Open	Open	Open	Open
128KB	1 & 2	Open	Open	Closed	Open	Closed	Open
256KB	2 & 3	Open	Closed	Closed	Closed	Closed	Open
512KB	1 & 2	Closed	Closed	Closed	Closed	Closed	Closed
Note:Pins designated should be in the closed position.

CPU TYPE CONFIGURATION
Type	OSC1	JP2	JP3	JP8	JP9	JP10
80486DX2- 50 MHz	50MHz	Closed	Closed	1 & 2, 3 & 4	2 & 3	1 & 2
80486DX2- 50 MHz	25MHz	Closed	Closed	1 & 2, 3 & 4	1 & 2	1 & 2
80486DX- 50 MHz	50MHz	Closed	Closed	1 & 2, 3 & 4	1 & 2	1 & 2
80486DX- 33 MHz	66MHz	Closed	Open	1 & 2, 3 & 4	2 & 3	1 & 2
80486DX- 33 MHz	33MHz	Closed	Open	1 & 2, 3 & 4	1 & 2	1 & 2
80486DX- 25 MHz	50MHz	Open	Open	1 & 2, 3 & 4	2 & 3	1 & 2
80486DX- 25 MHz	25MHz	Open	Open	1 & 2, 3 & 4	1 & 2	1 & 2
80486SX- 25 MHz	50MHz	Open	Open	2 & 3	2 & 3	Open
80486SX- 25 MHz	25MHz	Open	Open	2 & 3	1 & 2	Open
80486SX- 20 MHz	40MHz	Open	Open	2 & 3	2 & 3	Open
80486SX- 20 MHz	20MHz	Open	Open	2 & 3	1 & 2	Open
Note:Pins designated should be in the closed position.