80486-33 Motherboard Settings and Configuration

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

CONNECTIONS
Purpose	Location	Purpose	Location
External battery	J11	Turbo LED	JP11
Power LED & keylock	J20	Reset switch	SW1
Speaker	J21	Turbo switch	SW2

USER CONFIGURABLE SETTINGS
Function		Jumper	Position
»	CMOS memory normal operation	JP1	pins 2 & 3 closed
	CMOS memory clear	JP1	pins 1 & 2 closed
»	Monitor type select color	JP2	Closed
	Monitor type select monochrome	JP2	Open
»	Bus clock speed select ATCLK/4	JP6	Closed
	Bus clock speed select ATCLK/6	JP6	Open
»	CPU speed select double frequency clock	JP7	pins 2 & 3 closed
	CPU speed select single phase clock	JP7	pins 1 & 2 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

CACHE CONFIGURATION
Size	Bank 0	TAG
64KB	(8) 8K x 8	(1) 4K x 8
256KB	(8) 32K x 8	(1) 16K x 8

CACHE JUMPER CONFIGURATION
Size	JP8	JP9	JP10	JP12
64KB	Open	Open	Open	Open
256KB	Open	Closed	Closed	Closed

CPU TYPE CONFIGURATION
Type	JP3	JP4	JP5
80486SX	Open	Open	pins 2 & 3 closed
80486DX	pins 2 & 3 closed	Closed	pins 1 & 2 closed