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 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
IDE interface 2	J22	IDE interface LED	J40
IDE interface 1	J23	Riser Card	SL1
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
»	Flash BIOS write protect enabled	SW1/1	Off
	Flash BIOS write protect disabled	SW1/1	On
»	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	On
	system setup disabled	SW1/4	Off
»	Factory configured - do not alter	SW1/5	Off
»	Factory configured - do not alter	SW1/6	Off
»	Factory configured - do not alter	SW1/7	Off
»	Factory configured - do not alter	SW1/8	Off

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