Processor	80486SX/80486DX/ODP486SX/80486DX2/80486DX4/Pentium Overdrive
Processor Speed	25/33/50(internal)/66(internal)MHz
Chip Set	AST
Max. Onboard DRAM	128MB
Cache	64/256KB
BIOS	AMI
Dimensions	330mm x 218mm
I/O Options	Floppy drive interface, IDE interfaces (2), parallel port, PS/2 mouse port, serial ports (2), VGA feature connector, VGA port
NPU Options	None

CONNECTIONS
Purpose	Location	Purpose	Location
VGA port	CN1	External battery	J26
Parallel port	CN2	Speaker	J27
Serial port 2	CN3	Chassis fan power	J28
Serial port 1	CN4	Front panel connector	J29
PS/2 mouse port	CN5	Chassis fan power	J32
VGA feature connector	J19	IDE interface LED	J40
IDE interface 2	J22	Video memory upgrade slot	SL1
IDE interface 1	J23	Riser Card	SL2
Floppy drive interface	J24

USER CONFIGURABLE SETTINGS
Function		Jumper/Switch	Position
»	Cache type select write back	E1	Open
	Cache type select write through	E1	Closed
»	Factory configured - do not alter	E6	pins 1 & 2 closed
»	CMOS memory normal	E8	Open
	CMOS memory clear	E8	Closed
»	Video memory enabled	E800	Closed
	Video memory disabled	E800	Open
»	Flash BIOS write protect enabled	SW1/1	On
	Flash BIOS write protect disabled	SW1/1	Off
»	Password enabled	SW1/2	On
	Password disabled	SW1/2	Off
»	Monitor type select color	SW1/3	On
	Monitor type select monochrome	SW1/3	Off
»	System setup enabled	SW1/4	Off
	system setup disabled	SW1/4	On
»	On board video enabled	SW1/5	On
	On board video disabled	SW1/5	Off
»	Factory configured - do not alter	SW1/6	On
»	Factory configured - do not alter	SW1/7	On
»	Factory configured - do not alter	SW1/8	On

DRAM CONFIGURATION
Size	Bank 0	Bank 1	Bank 2	Bank 3
2MB	(1) 256K x 36	(1) 256K x 36	NONE	NONE
3MB	(1) 256K x 36	(1) 256K x 36	(1) 256K x 36	NONE
4MB	(1) 256K x 36	(1) 256K x 36	(1) 256K x 36	(1) 256K x 36
4MB	(1) 1M x 36	NONE	NONE	NONE
8MB	(1) 1M x 36	(1) 1M x 36	NONE	NONE
9MB	(1) 1M x 36	(1) 1M x 36	(1) 256K x 36	NONE
10MB	(1) 1M x 36	(1) 1M x 36	(1) 256K x 36	(1) 256K x 36
12MB	(1) 1M x 36	(1) 1M x 36	(1) 1M x 36	NONE
16MB	(1) 1M x 36	(1) 1M x 36	(1) 1M x 36	(1) 1M x 36
16MB	(1) 4M x 36	NONE	NONE	NONE
32MB	(1) 4M x 36	(1) 4M x 36	NONE	NONE
33MB	(1) 4M x 36	(1) 4M x 36	(1) 256K x 36	NONE
34MB	(1) 4M x 36	(1) 4M x 36	(1) 256K x 36	(1) 256K x 36
36MB	(1) 4M x 36	(1) 4M x 36	(1) 1M x 36	NONE
40MB	(1) 4M x 36	(1) 4M x 36	(1) 1M x 36	(1) 1M x 36
48MB	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36	NONE
49MB	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36	(1) 256K x 36
64MB	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36
64MB	(1) 8M x 36	(1) 8M x 36	NONE	NONE
65MB	(1) 8M x 36	(1) 8M x 36	(1) 256K x 36	NONE
66MB	(1) 8M x 36	(1) 8M x 36	(1) 256K x 36	(1) 256K x 36

DRAM CONFIGURATION (CON’T)
Size	Bank 0	Bank 1	Bank 2	Bank 3
68MB	(1) 8M x 36	(1) 8M x 36	(1) 1M x 36	NONE
72MB	(1) 8M x 36	(1) 8M x 36	(1) 1M x 36	(1) 1M x 36
96MB	(1) 8M x 36	(1) 8M x 36	(1) 8M x 36	NONE
128MB	(1) 8M x 36	(1) 8M x 36	(1) 8M x 36	(1) 8M x 36

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

CACHE JUMPER CONFIGURATION
Size	E5
64KB	Open
256KB	Closed

CPU TYPE CONFIGURATION
Type	E1	E2	E3	E4
80486SX (PQFP)	Open	pins 2 & 3 closed	pins 1 & 2 closed	Open
ODP486SX	Open	pins 2 & 3 closed	pins 1 & 2 closed	Open
80486DX (write back)	Open	pins 1 & 2 closed	pins 2 & 3 closed	Open
80486DX/DX2	Open	pins 1 & 2 closed	pins 1 & 2 closed	Open
80486DX4	Open	pins 1 & 2 closed	pins 1 & 2 closed	Open
Pentium Overdrive	Open	pins 2 & 3 closed	pins 2 & 3 closed	Open

CPU SPEED CONFIGURATION
Speed	E7	E9
25MHz	pins 1 & 2 closed	Closed
33MHz	pins 2 & 3 closed	Open
50iMHz	pins 1 & 2 closed	Closed
66iMHz	pins 2 & 3 closed	Open