Processor	80486SX/80486DX/80486DX2/80486DX4/Pentium Overdrive
Processor Speed	25/33/40/50(internal)/50/66(internal)/75(internal)/100(internal)MHz
Chip Set	OPTI
Max. Onboard DRAM	64MB
Cache	64/128/256KB
BIOS	AMI/ASI
Dimensions	330mm x 218mm
I/O Options	32-bit VESA local bus slots (2)
NPU Options	None

CONNECTIONS
Purpose	Location	Purpose	Location
Power LED & keylock	J19	Turbo LED	JP16
Turbo switch	JP14	Reset switch	S1
Speaker	JP15	32-bit VESA local bus slots	SL1 & SL2

USER CONFIGURABLE SETTINGS
Function		Jumper	Position
»	ASI password enabled	JP3	Closed
	ASI password disabled	JP3	Open
»	Flash BIOS write protect disabled	JP4	pins 2 & 3 closed
	Flash BIOS write protect enabled	JP4	pins 1 & 2 closed
»	Flash voltage select 5v	JP27	pins 1 & 2 closed
	Flash voltage select 12v	JP27	pins 2 & 3 closed
»	ASI/MR BIOS	JP36	Open
	AMI w/MEGAKEY keyboard control & CMOS memory clear	JP36	Closed
»	Local ready delay enabled	JP37	pins 1 & 2 closed
	Local ready = CPU ready enabled	JP37	pins 2 & 3 closed
»	CMOS memory normal operation	JP38	Open
	CMOS memory clear	JP38	Closed
»	Factory configured - do not alter	JP41	Open
»	Factory configured - do not alter	JP42	pins 1 & 2 closed
»	Factory configured - do not alter	JP43	Open
»	Factory configured - do not alter	JP45	pins 1 & 2 closed

DRAM CONFIGURATION
Size	Bank 0	Bank 1	Bank 2
2MB	(1) 512K x 36	NONE	NONE
4MB	(1) 512K x 36	(1) 512K x 36	NONE
4MB	(1) 1M x 36	NONE	NONE
6MB	(1) 512K x 36	(1) 512K x 36	(1) 512K x 36
6MB	(1) 512K x 36	(1) 1M x 36	NONE
8MB	(1) 1M x 36	(1) 1M x 36	NONE
8MB	(1) 2M x 36	NONE	NONE
10MB	(1) 512K x 36	(1) 2M x 36	NONE
12MB	(1) 1M x 36	(1) 1M x 36	(1) 1M x 36
12MB	(1) 1M x 36	(1) 2M x 36	NONE
12MB	(1) 512K x 36	(1) 512K x 36	(1) 2M x 36
14MB	(1) 512K x 36	(1) 1M x 36	(1) 2M x 36
16MB	(1) 2M x 36	(1) 2M x 36	NONE
16MB	(1) 1M x 36	(1) 1M x 36	(1) 2M x 36
16MB	(1) 4M x 36	NONE	NONE
18MB	(1) 512K x 36	(1) 2M x 36	(1) 2M x 36
20MB	(1) 1M x 36	(1) 4M x 36	NONE
20MB	(1) 1M x 36	(1) 2M x 36	(1) 2M x 36
24MB	(1) 2M x 36	(1) 2M x 36	(1) 2M x 36
24MB	(1) 1M x 36	(1) 1M x 36	(1) 4M x 36
32MB	(1) 2M x 36	(1) 2M x 36	(1) 4M x 36
32MB	(1) 8M x 36	NONE	NONE
32MB	(1) 4M x 36	(1) 4M x 36	NONE
40MB	(1) 1M x 36	(1) 1M x 36	(1) 8M x 36
48MB	(1) 2M x 36	(1) 2M x 36	(1) 8M x 36

DRAM CONFIGURATION (CON’T)
Size	Bank 0	Bank 1	Bank 2
48MB	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36
64MB	(1) 8M x 36	(1) 8M x 36	NONE
64MB	(1) 4M x 36	(1) 4M x 36	(1) 8M x 36
64MB	(1) 16M x 36	NONE	NONE

CACHE CONFIGURATION
Size	Bank 0	Bank 1	TAG (U1)	TAG (U2)
64KB	(4) 8K x 8	(4) 8K x 8	(1) 8K x 8	(1) 8K x 8
128KB	(4) 32K x 8	NONE	(1) 8K x 8	(1) 8K x 8
256KB	(4) 32K x 8	(4) 32K x 8	(1) 32K x 8	(1) 32K x 8

CACHE JUMPER CONFIGURATION
Size	JP11	JP13	JP25	JP26
64KB	pins 2 & 3 closed	pins 2 & 3 closed	Open	Open
128KB	pins 1 & 2 closed	pins 1 & 2 closed	Open	Closed
256KB	pins 2 & 3 closed	pins 2 & 3 closed	Closed	Closed

CPU TYPE CONFIGURATION
Type	JP20
80486SX	pins 1 & 2 closed
80486DX	pins 1 & 2, 3 & 4 closed
80486DX2	pins 1 & 2, 3 & 4 closed
80486DX4	pins 1 & 2, 3 & 4 closed
Pentium Overdrive	pins 1 & 2, 3 & 4 closed

CPU SPEED CONFIGURATION
Speed	JP5	JP6	JP7
25MHz	Open	Open	pins 1 & 2 closed
33MHz	Closed	Open	pins 1 & 2 closed
40MHz	Open	Closed	pins 1 & 2 closed
50iMHz	Open	Open	pins 1 & 2 closed
50MHz	Closed	Closed	pins 1 & 2 closed
66iMHz	Closed	Open	pins 1 & 2 closed
75iMHz	Open	Open	pins 2 & 3 closed
100iMHz	Closed	Open	pins 2 & 3 closed

CPU CLOCK SPEED CONFIGURATION (80486DX4)
Speed	JP39
1x	Open
2x	pins 1 & 2 closed
3x	pins 2 & 3 closed

CPU VOLTAGE CONFIGURATION
Speed	JP9	JP10	JP34	JP35
3.3v	Open	Open	Open	Open
5.0v	Closed	Closed	Closed	Closed

VESA WAIT STATE CONFIGURATION
Wait states	JP23
0 wait states	Open
1 wait state	Closed

BUS SPEED CONFIGURATION
CPU speed	JP24
<= 33MHz	Open
> 33MHz	Closed