4MAHL, 4DMU-50AHL Motherboard Settings and Configuration

Processor	CX486SX/CX487SX/80486SX/80486DX/ODP486SX/80486DX2
Processor Speed	20/25/33/40/50(internal)/50/66(internal)MHz
Chip Set	UMC
Max. Onboard DRAM	64MB
Cache	32/64/128/256KB
BIOS	AMI
Dimensions	330mm x 218mm
I/O Options	32-bit VESA local bus slots (2), floppy drive interface, game port, IDE interface (2), parallel port, serial ports (2)
NPU Options	None

CONNECTIONS
Purpose	Location	Purpose	Location
Serial port 2	CN2	Power LED & keylock	J8
Serial port 1	CN3	Reset switch	J9
Floppy drive interface	CN11	Game port	JP1
IDE interface	CN12	Turbo switch	JP31
AT bus hard drive interface	CN13	Turbo LED	JP32
Parallel port	CN14	Speaker	JP33
External battery	J1	32-bit VESA Local bus slot	S1
Hard drive LED (AT12)	J6	32-bit VESA Local bus slot	S2
AT bus hard drive LED	J7
Note:The exact location of J7 is unknown.

USER CONFIGURABLE SETTINGS
Function		Jumper	Position
»	HDD I/O CHRDY# disabled	J5	Open
	HDD I/O CHRDY# enabled	J5	Closed
»	Game port enabled	JP1	pins 1 & 2 closed
	Game port disabled	JP1	pins 2 & 3 closed
»	IDE interface disabled	JP3	pins 2 & 3 closed
	IDE interface enabled	JP3	pins 1 & 2 closed
»	Floppy drive interface enabled	JP4	pins 1 & 2 closed
	Floppy drive interface disabled	JP4	pins 2 & 3 closed
»	AT bus IDE interface or HDC enabled	JP6	pins 2 & 3 closed
	AT bus IDE interface or HDC disabled	JP6	pins 1 & 2 closed
»	Factory configured - do not alter	JP8	Closed
»	Factory configured - do not alter	JP9	Open
»	Factory configured - do not alter	JP10	N/A
»	AD12 local bus IDE HDD enabled	JP14	pins 2 & 3 closed
	AD12 local bus IDE HDD disabled	JP14	pins 1 & 2 closed
»	Factory configured - do not alter	JP15	pins 2 & 3 closed
»	Factory configured - do not alter	JP17	pins 2 & 3 closed
»	Factory configured - do not alter	JP18	pins 2 & 3 closed
	80486SX enabled	JP28	pins 1 & 2 closed
	Other CPU enabled	JP28	pins 2 & 3 closed
»	Factory configured - do not alter	JP29	pins 1 & 2 closed
»	Factory configured - do not alter	JP30	pins 1 & 2 closed
»	Factory configured - do not alter	JP35	pins 1 & 2 closed
»	Factory configured - do not alter	JP39	Open
»	Factory configured - do not alter	JP40	Open
»	Factory configured - do not alter	JP41	Open
»	Factory configured - do not alter	JP42	Open
»	Factory configured - do not alter	JP50	N/A
Note: JP28 is only configurable when you have a 80486SX PQFP mounted on the mainboard.
The exact location of JP41 is unknown.

SERIAL PORT CONFIGURATION
Port 1 (CN3)		JP7	JP5
»	COM1	Pins 1 & 2 closed	pins 1 & 2 closed
	COM3	Pins 2 & 3 closed	pins 1 & 2 closed
	Disabled	N/A	pins 2 & 3 closed

SERIAL PORT CONFIGURATION
Port 2 (CN2)		JP11	JP13
»	COM2	Pins 1 & 2 closed	pins 1 & 2 closed
	COM4	Pins 2 & 3 closed	pins 1 & 2 closed
	Disabled	N/A	pins 2 & 3 closed

PARALLEL PORT CONFIGURATION
Port		JP2	JP12
»	LPT2	pins 1 & 2 closed	pins 1 & 2 closed
	LPT3	pins 2 & 3 closed	pins 1 & 2 closed
	Disabled	N/A	pins 2 & 3 closed

DRAM CONFIGURATION
Size	Bank 0	Bank 1
1MB	(4) 256K x 9	NONE
1MB	NONE	(4) 256K x 9
2MB	(4) 256K x 9	(4) 256K x 9
4MB	(4) 1M x 9	NONE
4MB	NONE	(4) 1M x 9
5MB	(4) 1M x 9	(4) 256K x 9
5MB	(4) 256K x 9	(4) 1M x 9
8MB	(4) 1M x 9	(4) 1M x 9
16MB	(4) 4M x 9	NONE
16MB	NONE	(4) 4M x 9
17MB	(4) 4M x 9	(4) 256K x 9
17MB	(4) 256K x 9	(4) 4M x 9
20MB	(4) 4M x 9	(4) 1M x 9
20MB	(4) 1M x 9	(4) 4M x 9
32MB	(4) 4M x 9	(4) 4M x 9
64MB	(4) 16M x 9	NONE
64MB	NONE	(4) 16M x 9

CACHE CONFIGURATION
Size	Bank 0	Bank 1	TAG
64KB	(4) 8K x 8	(4) 8K x 8	(1) 8K x 8
128KB	(4) 32K x 8	NONE	(1) 8K x 8
256KB	(4) 32K x 8	(4) 32K x 8	(1) 32K x 8

CACHE JUMPER CONFIGURATION
Size	JP21	JP22	JP23	JP26	JP27
32KB	Open	Open	Open	Open	pins 2 & 3
64KB	Open	Open	Closed	Open	pins 1 & 2
128KB	Open	Closed	Closed	pins 1 & 2	pins 2 & 3
256KB	Closed	Closed	Closed	pins 2 & 3	pins 1 & 2
Note:Pins designated should be in the closed position.

CPU TYPE CONFIGURATION
Type	SW1/1	SW1/2	SW1/3	SW1/4	SW1/5	SW1/6	SW1/7
CX486SX	On	Off	On	Off	On	Off	Off
CX487SX	On	Off	On	Off	On	Off	Off
CX486S	Off	Off	Off	On	Off	Off	Off
80486SX	Off	Off	Off	On	Off	Off	Off
80486DX(PQFP)	On	Off	On	Off	On	On	On
80486DX	On	Off	On	Off	On	Off	Off
ODP486SX	On	On	Off	Off	On	Off	Off
80486DX2	On	Off	On	Off	On	Off	Off

CPU TYPE CONFIGURATION (CONT.)
Speed	JP47	JP49
CX486SX	N/A	pins 1 & 2 closed
CX487SX	N/A	N/A
CX486SX + CX487SX	Closed	pins 2 & 3 closed
CX486S	Open	pins 1 & 2 closed
80486SX	Open	pins 1 & 2 closed
80486DX(PQFP)	Open	pins 1 & 2 closed
80486DX	Open	pins 1 & 2 closed
ODP486SX	Open	pins 1 & 2 closed
80486DX2	Open	pins 1 & 2 closed
Note:The exact location of JP49 is unknown.

CPU SPEED CONFIGURATION
Speed	SW2/1	SW2/2	SW2/3	JP48
20MHz	Off	Off	Off	pins 2 & 3 closed
25MHz	On	Off	Off	pins 2 & 3 closed
33MHz	On	On	On	pins 2 & 3 closed
40MHz	On	On	Off	pins 1 & 2 closed
50i MHz	On	Off	Off	pins 1 & 2 closed
50MHz	Off	Off	On	pins 1 & 2 closed
66i MHz	On	On	On	pins 1 & 2 closed

VESA WAIT STATE/BUS SPEED CONFIGURATION
Speed	Wait states	JP36	JP37	JP38
<=33MHz	0 wait states	pins 1 & 2 closed	pins 1 & 2 closed	pins 1 & 2 closed
> 33MHz	1 wait state	pins 2 & 3 closed	pins 2 & 3 closed	pins 2 & 3 closed