Processor	80486SX/80486DX/80486DX2/Pentium Overdrive
Processor Speed	20/25/33/40/50/50(internal)/66(internal)/MHz
Chip Set	VIA
Max. Onboard DRAM	64MB
Cache	64/128/256/512/1024KB
BIOS	AMI
Dimensions	330mm x 218mm
I/O Options	32-bit VESA local bus slots (3)
NPU Options	None

CONNECTIONS
Purpose	Location	Purpose	Location
Reset switch	CN1	Turbo LED	CN4
Power LED & keylock	CN2	Turbo switch	CN5
Speaker	CN3	32 bit VESA local bus slots	SL1, SL2, SL3

USER CONFIGURABLE SETTINGS
Function		Jumper	Position
»	Factory configured - do not alter	J1	pins 1 & 2 closed
»	Fastgate A20 enabled	J2	pins 1 & 2 closed
	Fastgate A20 disabled	J2	pins 2 & 3 closed
»	One or more ISA busmastering devices on ISA bus	J10	pins 1 & 2 closed
	ISA busmastering system free	J10	pins 2 & 3 closed
»	Normal BIOS type operation	JP20	pins 1 & 2 closed
	Flash EPROM type BIOS enabled	JP20	pins 2 & 3 closed
»	Graphic accelerator cards without Weitek P9x00	JP21	pins 1 & 2 closed
	Graphic accelerator card with Weitek P9x00	JP21	pins 2 & 3 closed

DRAM CONFIGURATION
Size	Bank 0	Bank 1	Bank 2	Bank 3
1MB	(1) 256K x 36	NONE	NONE	NONE
2MB	(1) 512K x 36	NONE	NONE	NONE
2MB	(1) 256K x 36	(1) 256K x 36	NONE	NONE
4MB	(1) 1M x 36	NONE	NONE	NONE
4MB	(1) 512K x 36	NONE	(1) 512K x 36	NONE
8MB	(1) 2M x 36	NONE	NONE	NONE
8MB	(1) 1M x 36	(1) 1M x 36	NONE	NONE
16MB	(1) 4M x 36	NONE	NONE	NONE
16MB	(1) 2M x 36	NONE	(1) 2M x 36	NONE
32MB	(1) 8M x 36	NONE	NONE	NONE
32MB	(1) 4M x 36	NONE	(1) 4M x 36	NONE
64MB	(1) 8M x 36	NONE	(1) 8M x 36	NONE
64MB	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36

CACHE CONFIGURATION (WRITE-THROUGH CACHE)
Size	Bank 0	Bank 1	WTTAG	WBTAG
64KB	(4) 8K x 8	(4) 8K x 8	NONE	(1) 8K x 8
128KB	(4) 32K x 8	NONE	NONE	(1) 32K x 8
256KB	(4) 32K x 8	(4) 32K x 8	NONE	(1) 32K x 8
512KB	(4) 128K x 8	NONE	NONE	(1) 32K x 8
1M	(4) 128K x 8	(4) 128K x 8	NONE	(1) 128K x 8

CACHE CONFIGURATION (WRITE-BACK CACHE)
Size	Bank 0	Bank 1	WTTAG	WBTAG
64KB	(4) 8K x 8	(4) 8K x 8	(1) 8K x 8	(1) 8K x 8
128KB	(4) 32K x 8	NONE	(1) 32K x 8	(1) 32K x 8
256KB	(4) 32K x 8	(4) 32K x 8	(1) 32K x 8	(1) 32K x 8
512KB	(4) 128K x 8	NONE	(1) 32K x 8	(1) 32K x 8
1M	(4) 128K x 8	(4) 128K x 8	(1) 128K x 8	(1) 128K x 8

CACHE JUMPER CONFIGURATION
Size	JS1	JS2	JS3	JS4	JS5	JS6
64KB	1 & 2	1 & 2	1 & 2	1 & 2	1 & 2	1 & 2
128KB	2 & 3	2 & 3	1 & 2	1 & 2	1 & 2	1 & 2
256KB	2 & 3	2 & 3	2 & 3	1 & 2	1 & 2	1 & 2
512KB	2 & 3	2 & 3	2 & 3	2 & 3	2 & 3	1 & 2
1MB	2 & 3	2 & 3	2 & 3	2 & 3	2 & 3	2 & 3
Note:Pins designated should be in the closed position.

CPU TYPE CONFIGURATION
CPU Type	Speed	JC1	JC2	JC3	JK1	JK2
80486SX	20MHz	2 & 3	2 & 3	Open	1 & 2	1 & 2
80486SX	25MHz	2 & 3	2 & 3	Open	1 & 2	1 & 2
80486SX	33MHz	2 & 3	2 & 3	Open	1 & 2	1 & 2
80487SX	25MHz	1 & 2	1 & 2	2 & 3	1 & 2	1 & 2
80486DX	25MHz	1 & 2	1 & 2	1 & 2	1 & 2	1 & 2
80486DX	33MHz	1 & 2	1 & 2	1 & 2	1 & 2	1 & 2
80486DX	40MHz	1 & 2	1 & 2	1 & 2	1 & 2	1 & 2
80486DX	50MHz	1 & 2	1 & 2	1 & 2	2 & 3	2 & 3
80486DX2	50iMHz	1 & 2	1 & 2	1 & 2	1 & 2	1 & 2
80486DX2	66iMHz	1 & 2	1 & 2	2 & 3	1 & 2	1 & 2
Note:Pins designated should be in the closed position.

CPU TYPE CONFIGURATION (CON’T)
CPU Type	Speed	JV1	JV2	JK3A1	JK3B1
80486SX	20MHz	2 & 3	1 & 2	Closed	Closed
80486SX	25MHz	2 & 3	1 & 2	Open	Closed
80486SX	33MHz	2 & 3	1 & 2	Closed	Open
80487SX	25MHz	2 & 3	1 & 2	Open	Closed
80486DX	25MHz	2 & 3	1 & 2	Open	Closed
80486DX	33MHz	2 & 3	2 & 3	Closed	Open
80486DX	40MHz	2 & 3	2 & 3	Open	Open
80486DX	50MHz	2 & 3	1 & 2	Open	Closed
80486DX2	50iMHz	2 & 3	1 & 2	Open	Open
80486DX2	66iMHz	2 & 3	1 & 2	Closed	Closed
Note:Pins designated should be in the closed position.