DECPC LP Motherboard Settings and Configuration

Device Type	Mainboard
Processor	80486SX/80486DX/80486DX2
Processor Speed	25/33/50(internal)/66(internal)MHz
Chip Set	OPTI
Video Chip Set	Unidentified
Maximum Onboard Memory	64MB
Maximum Video Memory	1MB
Cache	64KB
BIOS	Unidentified
Dimensions	254mm x 218mm
I/O Options	Floppy drive interface, IDE interface, parallel port, PS/2 mouse port, serial ports (2), VGA feature connector, VGA port, riser slot
NPU Options	None

CONNECTIONS
Purpose	Location	Purpose	Location
VGA port	CN1	IDE interface	CN6
Parallel port	CN2	Floppy drive interface	CN7
Serial port 2	CN3	VGA feature connector	CN8
Serial port 1	CN4	CPU board connectors	CN9
PS/2 mouse port	CN5	Riser slot	SL1

USER CONFIGURABLE SETTINGS
Function		Label	Position
»	VGA IRQ9 disabled	J1	Open
	VGA IRQ9 enabled	J1	Closed
»	On board video disabled	J2	Open
	On board video enabled	J2	Closed
»	CMOS memory normal operation	J3	Pins 1 & 2 closed
	CMOS memory clear	J3	Pins 2 & 3 closed
	Reset switch enabled	J4	Closed
	Reset switch disabled	J4	Open
	Parallel port unidirectional	J5	Pins 1 & 2 closed
	Parallel port bidirectional	J5	Pins 2 & 3 closed
»	Factory configured - do not alter	J10	Open
»	Monitor type select color	J11	Closed
	Monitor type select monochrome	J11	Open
»	Factory configured - do not alter	J29	Open
»	Factory configured - do not alter	J30	Open
»	Factory configured - do not alter	J31	Open
	VGAIOW select local	J35	Pins 1 & 2 closed
	VGAIOW select local & ISA	J35	Pins 2 & 3 closed

SIMM CONFIGURATION
Size	Bank 0	Bank 1	Bank 2	Bank 3
4MB	(1) 1M x 36	None	None	None
8MB	(1) 2M x 36	None	None	None
8MB	(1) 1M x 36	(1) 1M x 36	None	None
12MB	(1) 2M x 36	(1) 1M x 36	None	None
12MB	(1) 1M x 36	(1) 1M x 36	(1) 1M x 36	None

SIMM CONFIGURATION (CON’T)
Size	Bank 0	Bank 1	Bank 2	Bank 3
12MB	(1) 1M x 36	(1) 2M x 36	None	None
16MB	(1) 4M x 36	None	None	None
16MB	(1) 2M x 36	(1) 1M x 36	(1) 1M x 36	None
16MB	(1) 2M x 36	(1) 2M x 36	None	None
16MB	(1) 1M x 36	(1) 1M x 36	(1) 1M x 36	(1) 1M x 36
20MB	(1) 4M x 36	(1) 1M x 36	None	None
20MB	(1) 2M x 36	(1) 1M x 36	(1) 1M x 36	(1) 1M x 36
20MB	(1) 1M x 36	(1) 2M x 36	(1) 2M x 36	None
20MB	(1) 1M x 36	(1) 4M x 36	None	None
24MB	(1) 4M x 36	(1) 1M x 36	(1) 1M x 36	None
24MB	(1) 4M x 36	(1) 2M x 36	None	None
24MB	(1) 2M x 36	(1) 2M x 36	(1) 2M x 36	None
24MB	(1) 2M x 36	(1) 4M x 36	None	None
28MB	(1) 4M x 36	(1) 1M x 36	(1) 1M x 36	(1) 1M x 36
32MB	(1) 8M x 36	None	None	None
32MB	(1) 4M x 36	(1) 4M x 36	None	None
32MB	(1) 2M x 36	(1) 2M x 36	(1) 2M x 36	(1) 2M x 36
36MB	(1) 8M x 36	(1) 1M x 36	None	None
40MB	(1) 8M x 36	(1) 1M x 36	(1) 1M x 36	None
40MB	(1) 8M x 36	(1) 2M x 36	None	None
40MB	(1) 4M x 36	(1) 2M x 36	(1) 2M x 36	(1) 2M x 36
40MB	(1) 2M x 36	(1) 4M x 36	(1) 4M x 36	None
40MB	(1) 2M x 36	(1) 8M x 36	None	None
44MB	(1) 8M x 36	(1) 1M x 36	(1) 1M x 36	(1) 1M x 36
48MB	(1) 8M x 36	(1) 2M x 36	(1) 2M x 36	None
48MB	(1) 8M x 36	(1) 4M x 36	None	None
48MB	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36	None
48MB	(1) 4M x 36	(1) 8M x 36	None	None
56MB	(1) 8M x 36	(1) 2M x 36	(1) 2M x 36	(1) 2M x 36
56MB	(1) 2M x 36	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36
64MB	(1) 8M x 36	(1) 4M x 36	(1) 4M x 36	None
64MB	(1) 8M x 36	(1) 8M x 36	None	None
64MB	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36

VIDEO MEMORY CONFIGURATION

Note: Board accepts 512KB/1MB of video memory. The configuration is unidentified.

VIDEO MEMORY JUMPER CONFIGURATION
Size	J28
512KB	Pins 1 & 2 closed
1MB	Pins 2 & 3 closed

CONNECTIONS
Purpose	Location
CPU board connectors	CN9

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

CACHE JUMPER CONFIGURATION
Size	J103	J104
128KB	Pins 1 & 2 closed	Pins 1 & 2 closed
256KB	Pins 2 & 3 closed	Pins 2 & 3 closed

CPU SPEED SELECTION
Speed	J109	J110	J111	J112
33MHz	Closed	Open	Open	Open
66iMHz	Closed	Open	Open	Open

CPU TYPE SELECTION
Type	J114	J115
80486SX	Pins 2 & 3 closed	Pins 2 & 3 closed
80486DX	Pins 1 & 2 closed	Pins 1 & 2 closed

CPU SECOND SOCKET SELECTION
Setting	J101	J102	J103
Not installed	Pins 1 & 2 closed	Pins 1 & 2 closed	Pins 1 & 2 closed
ODP486	Pins 1 & 2 closed	Pins 1 & 2 closed	Pins 1 & 2 closed
80486DX	Pins 2 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed
80486DX2	Pins 2 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed

CONNECTIONS
Purpose	Location
CPU board connectors	CN9

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

CACHE JUMPER CONFIGURATION
Size	J103	J104
128KB	Pins 1 & 2 closed	Pins 1 & 2 closed
256KB	Pins 2 & 3 closed	Pins 2 & 3 closed

CPU SPEED SELECTION
Speed	J109	J110	J111	J112
25MHz	Closed	Open	Open	Open
50iMHz	Closed	Open	Open	Open

CPU SECOND SOCKET SELECTION
Setting	J101	J102	J103
Not installed	Pins 1 & 2 closed	Pins 1 & 2 closed	Pins 1 & 2 closed
ODP486	Pins 1 & 2 closed	Pins 1 & 2 closed	Pins 1 & 2 closed
80486DX	Pins 2 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed
80486DX2	Pins 2 & 3 closed	Pins 2 & 3 closed	Pins 2 & 3 closed