MDE486 Motherboard Settings and Configuration

Processor	80486SX/80487SX/80486DX/ODP486SX/80486DX2
Processor Speed	20/25/33/50(internal)/50/66(internal)MHz
Chip Set	OPTI
Max. Onboard DRAM	128MB
Cache	64/128/256/512KB
BIOS	Mylex
Dimensions	330mm x 218mm
I/O Options	32-bit external memory card slot, floppy interface, IDE interface, parallel port, serial ports (2)
NPU Options	None

CONNECTIONS
Purpose	Location	Purpose	Location
32-bit external memory card	CN1	Reset switch	P2
Serial port 1	CN2	Speaker	P3
Serial port 2	CN3	Power LED & keylock	P4
Parallel port	CN4	Turbo LED	P5
IDE interface	CN5	IDE interface LED	P6
Floppy drive interface	CN6

USER CONFIGURABLE SETTINGS
Function		Jumper	Position
»	Factory configured - do not alter	J11	Open
»	Factory configured - do not alter	J12	Open
»	Factory configured - do not alter	J20	pins 2 & 3 closed
»	Factory configured - do not alter	J21	pins 1 & 2 closed
»	Monitor type select color	P1	Closed
	Monitor type select monochrome	P1	Open

DRAM CONFIGURATION
Size	Bank 0	Bank 1	Bank 2	Bank 3
4MB	(4) 256K x 36	NONE	NONE	NONE
8MB	(4) 256K x 36	(4) 256K x 36	NONE	NONE
12MB	(4) 256K x 36	(4) 256K x 36	(4) 256K x 36	NONE
16MB	(4) 256K x 36	(4) 256K x 36	(4) 256K x 36	(4) 256K x 36
16MB	(4) 1M x 36	NONE	NONE	NONE
20MB	(4) 1M x 36	(4) 256K x 36	NONE	NONE
24MB	(4) 1M x 36	(4) 256K x 36	(4) 256K x 36	NONE
28MB	(4) 1M x 36	(4) 256K x 36	(4) 256K x 36	(4) 256K x 36
32MB	(4) 1M x 36	(4) 1M x 36	NONE	NONE
36MB	(4) 1M x 36	(4) 1M x 36	(4) 256K x 36	NONE
40MB	(4) 1M x 36	(4) 1M x 36	(4) 256K x 36	(4) 256K x 36
48MB	(4) 1M x 36	(4) 1M x 36	(4) 1M x 36	NONE
52MB	(4) 1M x 36	(4) 1M x 36	(4) 1M x 36	(4) 256K x 36
64MB	(4) 1M x 36	(4) 1M x 36	(4) 1M x 36	(4) 1M x 36
64MB	(4) 4M x 36	NONE	NONE	NONE
128MB	(4) 4M x 36	(4) 4M x 36	NONE	NONE
192MB	(4) 4M x 36	(4) 4M x 36	(4) 4M x 36	NONE
256MB	(4) 4M x 36	(4) 4M x 36	(4) 4M x 36	(4) 4M x 36
Note:Banks 2 and 3 are used when a 32-bit external memory card is installed at CN1.

CACHE CONFIGURATION
Size	Bank 0	Bank 1	TAG (U19)	TAG (U20)
64KB	(4) 8K x 8	(4) 8K x 8	(1) 8K x 8	NONE
128KB	(4) 32K x 8	NONE	(1) 8K x 8	NONE
256KB	(4) 32K x 8	(4) 32K x 8	(1) 8K x 8	(1) 8K x 8
512KB	(4) 128K x 8	NONE	(1) 32K x 8	NONE

CACHE JUMPER CONFIGURATION
Size	J1	J2	J3	J4	J5	J6	J8
64KB	Open	Open	Open	Open	Open	Open	2 & 3
128KB	Open	Open	Closed	Open	Closed	Open	1 & 2
256KB	Open	Closed	Closed	Closed	Closed	Open	2 & 3
512KB	Closed	Closed	Closed	Closed	Closed	Closed	1 & 2
Note: Pins designated should be in the closed position.

CPU TYPE CONFIGURATION
Type	J9	J10
80486SX	Open	pins 1 & 2, 3 & 4 closed
ODP486SX	pins 1 & 2 closed	pins 2 & 3 closed
80487SX	pins 1 & 2 closed	pins 2 & 3 closed
80486DX	pins 2 & 3 closed	pins 1 & 2, 3 & 4 closed
80486DX2	pins 2 & 3 closed	pins 1 & 2, 3 & 4 closed

CPU SPEED CONFIGURATION
Speed	J7	J13	J14	J15	J16	J17	J18	J19
20MHz	Closed	Open	Open	Closed	Open	Open	1 & 2	1 & 2
25MHz	Open	Closed	Closed	Open	Open	Open	1 & 2	2 & 3
33MHz	Open	Open	Closed	Open	Closed	Open	1 & 2	2 & 3
50iMHz	Open	Closed	Closed	Open	Open	Open	1 & 2	2 & 3
50MHz	Open	Open	Open	Open	Closed	Closed	2 & 3	2 & 3
66iMHz	Open	Open	Closed	Open	Closed	Open	1 & 2	2 & 3
Note: Pins designated should be in the closed position.