486 SYSTEM Motherboard Settings and Configuration

Processor	80486SX/80486DX/80486DX2
Processor Speed	25/33/50(internal)/66(internal)MHz
Chip Set	Intel
Max. Onboard DRAM	36MB
Cache	64/128/256KB
BIOS	Phoenix
Dimensions	330mm x 218mm
I/O Options	32-bit riser card, floppy drive interface, IDE interface, parallel port, PS/2 mouse port, serial ports (2), VGA feature connector, VGA port
NPU Options	None

CONNECTIONS
Purpose	Location	Purpose	Location
VESA control PAL chips	C1	Floppy drive interface	CN8
VGA port	CN1	IDE interface	CN9
Parallel port	CN2	VGA feature connector	CN10
Serial port 1	CN3	Multifunction connector	CN11
Serial port 2	CN4	Reset switch	CN12
PS/2 mouse port	CN5	IDE interface LED	CN13
Power controller box connector	CN6	EPA power saving relay	CN14
Power saving controller connector	CN7	Riser Card	SL1

USER CONFIGURABLE SETTINGS
Function		Jumper	Position
»	CMOS memory normal operation	J2	pins 1 & 2 closed
	CMOS memory clear	J2	pins 2 & 3 closed
»	On board battery enabled	J13	Closed
	On board battery disabled	J13	Open
»	DRAM parity disabled	J14	Closed
	DRAM parity enabled	J14	Open
»	On board VGA enabled	J20	pins 1 & 2 closed
	On board VGA disabled	J20	pins 2 & 3 closed
»	Keylock disabled	J27	pins 1 & 2 closed
	Keylock enabled	J27	pins 2 & 3 closed
»	On board memory enabled	J28	pins 1 & 2 closed
	On board memory disabled	J28	pins 2 & 3 closed
»	Floppy/hard drive controller enabled	J29	Closed
	Floppy/hard drive controller disabled	J29	Open

DRAM CONFIGURATION
Size	Bank 0	Bank 1	Bank 2
4MB	(4) 44256	NONE	NONE
8MB	(4) 44256	(1) 1M x 36	NONE
12MB	(4) 44256	(1) 1M x 36	(1) 1M x 36
12MB	(4) 44256	(1) 2M x 36	NONE
16MB	(4) 44256	(1) 1M x 36	(1) 2M x 36
20MB	(4) 44256	(1) 4M x 36	NONE
20MB	(4) 44256	(1) 2M x 36	(1) 2M x 36
24MB	(4) 44256	(1) 1M x 36	(1) 4M x 36
36MB	(4) 44256	(1) 4M x 36	(1) 4M x 36
Note: Bank 0 and parity chips are factory installed and are non configurable.

CACHE CONFIGURATION
Size	Bank 0	Bank 1	TAG (7 bit)	TAG (8 bit)
64KB	(4) 8K x 8	(4) 8K x 8	(1) 8K x 8	(1) 16K x 4
128KB	(4) 32K x 8	NONE	(1) 8K x 8	(1) 16K x 4
256KB	(4) 32K x 8	(4) 32K x 8	(1) 32K x 8	(1) 16K x 4

CACHE JUMPER CONFIGURATION
Size	J5	J6	J23	J24
64KB	pins 2 & 3 closed	pins 2 & 3 closed	N/A	pins 1 & 2 closed
128KB	pins 1 & 2 closed	pins 2 & 3 closed	pins 2 & 3 closed	pins 2 & 3 closed
256KB	pins 1 & 2 closed	pins 1 & 2 closed	pins 1 & 2 closed	pins 2 & 3 closed

CACHE JUMPER CONFIGURATION (TAG)
Type	J5	J6	J24
Write through	N/A	pins 2 & 3 closed	N/A
Write back/7 bit	pins 2 & 3 closed	pins 1 & 2 closed	Open
Write back/8 bit	pins 1 & 2 closed	pins 2 & 3 closed	Closed

CPU TYPE CONFIGURATION
Type	J9	J10	J11
80486SX (PQFP)	Open	Closed	Open
80486SX (PGA)	Open	Open	Open
80487SX	Open	Closed	Closed
80486DX/DX2	Closed	Closed	Open

CPU SPEED CONFIGURATION
Speed	J17
25MHz	pins 3 - 7 closed
33MHz	pins 4 - 8 closed
50iMHz	pins 2 - 5 closed
66iMHz	pins 3 - 6 closed

VIDEO MEMORY CONFIGURATION
Size	Bank 0	Bank 1
512KB	(4) 256K x 4	NONE
1MB	(4) 256K x 4	(4) 256K x 4
Note: Bank 0 is factory installed and is non configurable.