486 SYSTEM (V20) Motherboard Settings and Configuration

Processor	AM486SX/(SL)AM486SX/80486SX/AM486DX/(SL)AM486DX/80486DX/CX486DX2/AM486DX2(SL)AM486DX2/80486DX2/AM486DX4/ (SL)AM486DX4/80486DX4/P24D/P24T
Processor Speed	25/33/40/50(internal)/50/66(internal)/75(internal)/100(internal)MHz
Chip Set	Unidentified
Video Chip Set	None
Maximum Onboard Memory	64MB
Maximum Video Memory	None
Cache	128/256/512KB
BIOS	Unidentified
Dimensions	330mm x 218mm
I/O Options	32-bit VESA local bus slot, 32-bit PCI slots (3), floppy drive interface, green PC connector, IDE interfaces (2), parallel port, PS/2 mouse port, serial ports (2)
NPU Options	None

CONNECTIONS
Purpose	Location	Purpose	Location
Serial port 1	CN1	Reset switch/green PC connector	CN9 pins 7 & 8
Serial port 2	CN2	Power LED & keylock	CN10 pins 1 - 5
Parallel port	CN3	Speaker	CN10 pins 7 - 10
Floppy drive interface	CN4	Turbo LED	CN10 pins 12 & 13
IDE interface 1	CN5	Turbo switch	CN10 pins 15 - 17
IDE interface 2	CN6	Reset switch	CN10 pins 19 & 20
PS/2 mouse port	CN7	32-bit PCI slots	PC1 - PC3
IDE interface LED	CN8	32-bit VESA local bus slots	SL1
Power LED & keylock	CN9 pins 1 - 4

USER CONFIGURABLE SETTINGS
Function		Label	Position
»	Password disabled	JP1	Pins 2 & 3 closed
	Password enabled	JP1	Pins 1 & 2 closed
»	OEM BIOS enabled	JP2	Pins 2 & 3 closed
»	Factory configured - do not alter	JP2	Pins 1 & 2 closed
»	M5115 I/O enabled	JP8	Pins 1 & 2 closed
	M5115 I/O disabled	JP8	Pins 2 & 3 closed
	Jumper information unidentified	JP10	Unidentified
»	Local bus IDE I/O address select 0FXH	JP11	Pins 1 & 2 closed
	Local bus IDE I/O address select 07XH	JP11	Pins 2 & 3 closed
»	M5213N local bus IDE enabled	JP12	Pins 2 & 3 closed
	M5213N local bus IDE disabled	JP12	Pins 1 & 2 closed
»	Reset key enabled	JP23	Pins 1 & 2 closed
	Reset key disabled	JP23	Pins 2 & 3 closed
»	Green PC connector enabled	JP24	Pins 2 & 3 closed
	Reset switch enabled	JP24	Pins 1 & 2 closed
»	Factory configured - do not alter	JP41	Pins 2 & 3 closed

DRAM CONFIGURATION
Size	Bank 0	Bank 1	Bank 2	Bank 3
4MB	None	None	None	(1) 1M x 36
8MB	(1) 2M x 36	None	None	None
8MB	None	None	(1) 1M x 36	(1) 1M x 36
8MB	None	None	(1) 2M x 36	None
12MB	(1) 2M x 36	None	(1) 1M x 36	None
12MB	(1) 2M x 36	None	None	(1) 1M x 36
12MB	None	(1) 1M x 36	(1) 1M x 36	(1) 1M x 36
12MB	(1) 1M x 36	None	(1) 2M x 36	None
12MB	None	(1) 1M x 36	(1) 2M x 36	None
16MB	(1) 2M x 36	None	(1) 2M x 36	None
16MB	(1) 2M x 36	None	(1) 1M x 36	(1) 1M x 36

DRAM CONFIGURATION (CON’T)
Size	Bank 0	Bank 1	Bank 2	Bank 3
16MB	(1) 1M x 36	(1) 1M x 36	(1) 1M x 36	(1) 1M x 36
16MB	None	None	None	(1) 4M x 36
16MB	(1) 1M x 36	(1) 1M x 36	(1) 2M x 36	None
24MB	(1) 2M x 36	None	(1) 4M x 36	None
24MB	(1) 2M x 36	None	None	(1) 4M x 36
24MB	(1) 4M x 36	None	(1) 2M x 36	None
24MB	None	(1) 4M x 36	(1) 2M x 36	None
28MB	(1) 2M x 36	None	(1) 4M x 36	(1) 1M x 36
28MB	(1) 2M x 36	None	(1) 1M x 36	(1) 4M x 36
28MB	(1) 4M x 36	(1) 1M x 36	(1) 2M x 36	None
28MB	(1) 1M x 36	(1) 4M x 36	(1) 2M x 36	None
32MB	None	None	(1) 4M x 36	(1) 4M x 36
40MB	(1) 2M x 36	None	(1) 4M x 36	(1) 4M x 36
40MB	(1) 4M x 36	(1) 4M x 36	(1) 2M x 36	None
48MB	None	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36
64MB	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36

CACHE CONFIGURATION
Size	Bank 0	Bank 1	TAG
128KB	(4) 32K x 8	None	(1) 32K x 8
256KB	(4) 32K x 8	(4) 32K x 8	(1) 32K x 8
512KB	(4) 128K x 8	None	(1) 32K x 8

CACHE JUMPER CONFIGURATION
Size	JP13	JP15	JP16
128KB	Pins 2 & 3 closed	Pins 2 & 3 closed	Pins 1 & 2 closed
256KB	Pins 2 & 3 closed	Pins 1 & 2 closed	Pins 2 & 3 closed
512KB	Pins 1 & 2 closed	Pins 1 & 2 closed	Pins 1 & 2 closed

CPU SPEED SELECTION
Speed	JP17	JP21
25MHz	Pins 1 & 5 closed	Pins 2 & 3 closed
33MHz	Pins 2 & 6 closed	Pins 2 & 3 closed
40MHz	Pins 3 & 7 closed	Pins 1 & 2 closed
50iMHz	Pins 1 & 5 closed	Pins 2 & 3 closed
50MHz	Pins 4 & 8 closed	Pins 1 & 2 closed
66iMHz	Pins 2 & 6 closed	Pins 2 & 3 closed
75iMHz	Pins 1 & 5 closed	Pins 2 & 3 closed
100iMHz	Pins 2 & 6 closed	Pins 2 & 3 closed

CPU TYPE SELECTION
Type	JP9	JP20	JP26	JP27
AM486SX	Pins 2 & 3 closed	Pins 1 & 2 closed	Pins 1 & 2 closed	Pins 1 & 2 closed
(SL)AM486SX	Pins 1 & 2 closed	Pins 1 & 2 closed	Pins 1 & 2 closed	Pins 1 & 2 closed
80486SX	Pins 2 & 3 closed	Pins 1 & 2 closed	Pins 2 & 3 closed	Pins 2 & 3 closed
AM486DX	Pins 2 & 3 closed	Pins 1 & 2 closed	Pins 1 & 2 closed	Pins 1 & 2 closed
(SL)AM486DX	Pins 1 & 2 closed	Pins 1 & 2 closed	Pins 1 & 2 closed	Pins 1 & 2 closed
80486DX	Pins 2 & 3 closed	Pins 1 & 2 closed	Pins 2 & 3 closed	Pins 2 & 3 closed
CX486DX2	Pins 2 & 3 closed	Pins 1 & 2 closed	Pins 2 & 3 closed	Open
AM486DX2	Pins 2 & 3 closed	Pins 1 & 2 closed	Pins 1 & 2 closed	Pins 1 & 2 closed
(SL)AM486DX2	Pins 1 & 2 closed	Pins 1 & 2 closed	Pins 1 & 2 closed	Pins 1 & 2 closed
80486DX2	Pins 2 & 3 closed	Pins 1 & 2 closed	Pins 2 & 3 closed	Pins 2 & 3 closed
AM486DX4	Pins 2 & 3 closed	Pins 1 & 2 closed	Pins 1 & 2 closed	Pins 1 & 2 closed
(SL)AM486DX4	Pins 1 & 2 closed	Pins 1 & 2 closed	Pins 1 & 2 closed	Pins 1 & 2 closed
80486DX4	Pins 2 & 3 closed	Pins 1 & 2 closed	Pins 2 & 3 closed	Pins 2 & 3 closed
P24D	Pins 2 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed
P24T	Pins 2 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed

CPU TYPE SELECTION (CON’T)
Type	JP33	JP34	JP35	JP37
AM486SX	Pins 1 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed
(SL)AM486SX	Pins 1 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed
80486SX	Pins 1 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed
AM486DX	Pins 1 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed
(SL)AM486DX	Pins 1 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed
80486DX	Pins 1 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed
CX486DX2	Pins 2 & 4 closed	Pins 1 & 2 closed	Pins 2 & 3 closed	Pins 1 & 2 closed
AM486DX2	Pins 1 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed
(SL)AM486DX2	Pins 1 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed
80486DX2	Pins 1 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed
AM486DX4	Pins 1 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed
(SL)AM486DX4	Pins 1 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed
80486DX4	Pins 1 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed
P24D	Pins 1 & 3 closed	Pins 2 & 3 closed	Pins 1 & 2 closed	Pins 2 & 3 closed
P24T	Pins 1 & 3 closed	Pins 2 & 3 closed	Pins 1 & 2 closed	Pins 2 & 3 closed

CPU MULTIPLIER SELECTION (80486DX4 ONLY)
» Multiplier		JP22
»	2x	Pins 3 & 4 closed
»	2.5x	Pins 2 & 3 closed
»	3x	Pins 1 & 2 closed