SPECTRUM II 486 PCI/ISA/VESA Motherboard Settings and Configuration

Processor	CX486SX/AM486SX/80486SX/CX486DX/AM486DX/80486DX/ CX486DX2/AM486DX2/80486DX2/CX486DX4/AM486DX4/80486DX4
Processor Speed	25/33/40/50(internal)/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	AMI/Award/MR BIOS
Dimensions	254mm x 218mm
I/O Options	32-bit VESA local bus slots (2), 32-bit PCI slots (4)
NPU Options	None

CONNECTIONS
Purpose	Location	Purpose	Location
Turbo switch	J1	Power LED & keylock	J5
Turbo LED	J2	32-bit PCI slots	PC1 – PC4
Speaker	J3	32-bit VESA local bus slots	SL1 & SL2
Reset switch	J4

USER CONFIGURABLE SETTINGS
Function		Label	Position
»	CMOS memory normal operation	JP2	Pins 1 & 2 closed
	CMOS memory clear	JP2	Pins 2 & 3 closed
»	Factory configured - do not alter	JP10A	Open
»	Factory configured - do not alter	JP10B	Pins 1 & 2 closed
»	Factory configured - do not alter	JP10C	Pins 2 & 3 closed
»	Factory configured - do not alter	JP10D	Open
»	Factory configured - do not alter	JP10E	Open
»	Factory configured - do not alter	JP38A	Open
»	Factory configured - do not alter	JP38B	Pins 1 & 2 closed
»	Factory configured - do not alter	JP38C	Pins 2 & 3 closed
	IDE type select PCI IDE	JP38D	Closed
	IDE type select VESA IDE	JP38D	Open

DRAM CONFIGURATION
Size	Bank 0	Bank 1	Bank 2	Bank 3
1MB	(1) 256K x 36	None	None	None
2MB	(1) 256K x 36	(1) 256K x 36	None	None
2MB	(1) 512K x 36	None	None	None
3MB	(1) 256K x 36	(1) 512K 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) 512K x 36	(1) 512K x 36	None	None
4MB	(1) 1M x 36	None	None	None
5MB	(1) 256K x 36	(1) 1M x 36	None	None
5MB	(1) 256K x 36	(1) 256K x 36	(1) 256K x 36	(1) 512K x 36
6MB	(1) 512K x 36	(1) 1M x 36	None	None
8MB	(1) 1M x 36	(1) 1M x 36	None	None
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) 2M x 36	(1) 2M x 36	None	None

DRAM CONFIGURATION (CON’T)
Size	Bank 0	Bank 1	Bank 2	Bank 3
16MB	(1) 4M x 36	None	None	None
32MB	(1) 4M x 36	(1) 4M x 36	None	None
48MB	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36	None
64MB	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36
Note: Board accepts x 32 SIMMs.

DRAM JUMPER CONFIGURATION
Setting	JP23
1 BK installed	Pins 1 & 2 closed
2 BK installed	Pins 2 & 3 closed

CACHE CONFIGURATION
Size	Bank 0	TAG
128KB	(4) 32K x 8	(1) 8K x 8
256KB	(2) 64K x 32	(1) 32K x 8
512KB	(4) 128K x 8	(1) 32K x 8

CACHE JUMPER CONFIGURATION
Size	JP20
128KB	Pins 1 & 2 closed
256KB	Pins 1 & 2 closed
512KB	Pins 2 & 3 closed

CPU SPEED SELECTION
Speed	JP7	JP27	JP28
25MHz	Closed	Pins 1 & 2 closed	Pins 2 & 3 closed
33MHz	Open	Pins 2 & 3 closed	Pins 1 & 2 closed
50iMHz	Closed	Pins 1 & 2 closed	Pins 2 & 3 closed
66iMHz	Open	Pins 2 & 3 closed	Pins 1 & 2 closed
75iMHz	Closed	Pins 1 & 2 closed	Pins 2 & 3 closed
100iMHz	Open	Pins 2 & 3 closed	Pins 1 & 2 closed

CPU TYPE SELECTION
Type	JP11
Cyrix	Pins 2 & 3 closed
AMD	Pins 1 & 2 closed
Intel	Pins 1 & 2 closed

CPU TYPE SELECTION
Type	JP99
All CPU types	Closed
DX4 only	Open

FLASH BIOS VOLTAGE SELECTION
Voltage	JP12	JP80
5v	Pins 1 & 2 closed	Pins 1 & 3, 2 & 4 closed
12v	Pins 2 & 3 closed	Pins 3 & 5, 4 & 6 closed