Processor	80486SX/80487SX/80486DX
Processor Speed	20/25/33/40/50MHz
Chip Set	OPTI
Max. Onboard DRAM	128MB
Cache	64/128/256/512KB
BIOS	AMI/Phoenix
Dimensions	330mm x 218mm
I/O Options	None
NPU Options	4167

CONNECTIONS
Purpose	Location	Purpose	Location
Speaker	J4	Turbo LED	J7
Power LED & keylock	J5	Reset switch	S9
Turbo switch	J6

USER CONFIGURABLE SETTINGS
Function		Jumper	Position
»	Snooping/flush select 20MHz	JP8	Closed
	Snooping/flush select 25/33/40/50MHz	JP8	Open
»	Monitor type select color	JP9	Closed
	Monitor type select monochrome	JP9	Open
»	CPU speed select iOSC/1	JP12	pins 1 & 2 closed
	CPU speed select iOCS/2	JP12	pins 2 & 3 closed

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
64MB	(4) 16M x 9	NONE
128MB	(4) 16M x 9	(4) 16M x 9

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
512KB	(4) 128K x 8	NONE

CACHE TAG CONFIGURATION
Size	TAG (U54)	TAG (U55)	TAG (U56)	TAG (U72)
64KB	(1) 64K x 1	(1) 8K x 8	NONE	(1) 64K x 1
128KB	(1) 64K x 1	(1) 8K x 8	NONE	(1) 64K x 1
256KB	(1) 64K x 1	(1) 8K x 8	(1) 8K x 8	(1) 64K x 1
512KB	(1) 64K x 1	(1) 32K x 8	NONE	(1) 64K x 1

CACHE JUMPER CONFIGURATION
Size	JP2	JP3	JP4	JP5	JP16	JP17	JP18
64KB	2 & 3	Open	Open	Open	Open	Open	Open
128KB	1 & 2	Closed	Closed	Open	Closed	Open	Open
256KB	2 & 3	Closed	Closed	Open	Closed	Open	Closed
512KB	1 & 2	Closed	Closed	Closed	Closed	Closed	Closed
Note: Pins designated should be in the closed position.

CPU TYPE CONFIGURATION
Type	JP1	JP10	JP11
80486SX	pins 2 & 3 closed	pins 2 & 3 closed	Open
80487SX	pins 2 & 3 closed	pins 1 & 2, 3 & 4 closed	pins 1 & 2 closed
80486DX	pins 1 & 2 closed	pins 1 & 2, 3 & 4 closed	pins 2 & 3 closed

CPU SPEED CONFIGURATION
Speed	JP6	JP7
20MHz	Open	Open
25MHz	Open	Open
33MHz	Open	Closed
40MHz	Closed	Open
50MHz	Closed	Closed