Processor	80486SX/80487SX/80486DX/P23T
Processor Speed	16/20/25/33MHz
Chip Set	Symphony
Max. Onboard DRAM	32MB
Cache	64/256KB
BIOS	AMI/DTK
Dimensions	330mm x 222mm
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
Reset switch	J1	Serial port 2	J28
Turbo LED	J2	Floppy drive interface	J35
Turbo switch	J3	IDE interface	J36
Power LED & keylock	J5	IDE interface LED	J37
VGA feature connector	J23	Parallel port	J47
VGA port	J24	PS/2 mouse port	J48
Serial port 1	J25	Riser slot	SL1

USER CONFIGURABLE SETTINGS
Function		Jumper	Position
»	Cache write hit wait state select 0 wait states	J8	Closed
	Cache write hit wait state select 1 wait state	J8	Open
»	On board VGA wait state select 0 wait states	J27	Closed
	On board VGA wait state select 1 wait state	J27	Open
»	VGA and system BIOS combined	J29	Closed
	VGA and system BIOS not combined	J29	Open
»	Parallel port IRQ select IRQ7	J32	pins 2 & 3 closed
	Parallel port IRQ select IRQ5	J32	pins 1 & 2 closed
»	Monitor type select monochrome	J33	Closed
	Monitor type select color	J33	Open
	Floppy drive interface enabled	J46	pins 1 & 2 closed
	Floppy drive interface disabled	J46	pins 2 & 3 closed
»	Cache enabled	J50	Closed
	Cache disabled	J50	Open
»	VGA KHz select 31.5KHz	SW1/5	Off
	VGA KHz select 35KHz	SW1/5	On

DRAM CONFIGURATION
Size	Bank 0	Bank 1
1MB	(4) 256K x 9	NONE
2MB	(4) 256K x 9	(4) 256K x 9
4MB	(4) 1M x 9	NONE
5MB	(4) 256K x 9	(4) 1M x 9
5MB	(4) 1M x 9	(4) 256K x 9
8MB	(4) 1M x 9	(4) 1M x 9
16MB	(4) 4M x 9	NONE
17MB	(4) 256K x 9	(4) 4M x 9
17MB	(4) 4M x 9	(4) 256K x 9
20MB	(4) 1M x 9	(4) 4M x 9
20MB	(4) 4M x 9	(4) 1M x 9
32MB	(4) 4M x 9	(4) 4M x 9

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

CACHE JUMPER CONFIGURATION
Size	J7	J10	J11
64KB	pins 1 & 2 closed	pins 1 & 2 closed	pins 1 & 2 closed
128KB	pins 2 & 3 closed	pins 2 & 3 closed	pins 2 & 3 closed

CPU TYPE CONFIGURATION
Type	J9	J16	J17
80486SX	Open	pins 2 & 3 closed	Open
80486DX	pins 1 & 2 closed	pins 1 & 2 closed	Closed
Note: An 80478SX or P23T can be installed at CPU1.

CPU SPEED CONFIGURATION
Speed	J18	J19	J21	J51
16MHz	Closed	Closed	pins 2 & 3 closed	Open
20MHz	Closed	Open	pins 2 & 3 closed	Open
25MHz	Open	Open	pins 2 & 3 closed	Open
33MHz	Open	Closed	pins 2 & 3 closed	Open

IDE CONFIGURATION
Setting	J52	J53
Enabled	Closed	Closed
Disabled	Open	Open

PARALLEL PORT CONFIGURATION
LPT	J39	J40
LPT1	pins 2 & 3 closed	pins 1 & 2 closed
LPT2	pins 1 & 2 closed	pins 1 & 2 closed
LPT3	pins 1 & 2 closed	pins 2 & 3 closed
Disabled	pins 2 & 3 closed	pins 2 & 3 closed

SERIAL PORT CONFIGURATION
Port 1	Port 2	J41	J42	J43
COM1	COM2	pins 1 & 2 closed	pins 1 & 2 closed	pins 1 & 2 closed
COM1	Disabled	pins 1 & 2 closed	pins 2 & 3 closed	pins 1 & 2 closed
Disabled	COM2	pins 1 & 2 closed	pins 1 & 2 closed	pins 2 & 3 closed
COM2	COM1	pins 2 & 3 closed	pins 1 & 2 closed	pins 1 & 2 closed
COM2	Disabled	pins 2 & 3 closed	pins 2 & 3 closed	pins 1 & 2 closed
Disabled	COM1	pins 2 & 3 closed	pins 1 & 2 closed	pins 2 & 3 closed
Disabled	Disabled	pins 1 & 2 closed	pins 2 & 3 closed	pins 2 & 3 closed
Disabled	Disabled	pins 2 & 3 closed	pins 2 & 3 closed	pins 2 & 3 closed

SERIAL PORT IRQ CONFIGURATION
IRQ	J30	J31
IRQ3	Closed	Open
IRQ4	Open	Closed

ON BOARD VGA CONFIGURATION
Setting	J15	J26
Enabled	Open	pins 1 & 2 closed
Disabled	Closed	pins 2 & 3 closed

VGA REFRESH CONFIGURATION (800 X 600)
Setting		SW1/3	SW1/4
»	50Hz	Off	Off
	56Hz	On	On
	60Hz	Off	On
	72Hz	On	Off

VGA REFRESH CONFIGURATION (1024 X 728)
Setting		SW1/1	SW1/2
»	Interlaced	Off	Off
	60Hz	On	Off
	70Hz	Off	On
	Interlaced	On	On

VRAM CONFIGURATION
Size	Bank 0	Bank 1
512KB	(4) 256K x 16	NONE
1MB	(4) 256K x 16	(4) 256K x 16
Note: Bank 0 is factory installed and is not configurable.

VRAM SWITCH CONFIGURATION
Size	SW1/6
512KB	On
1MB	Off
Note: Bank 0 is factory installed and is not configurable.