BARRACUDA Motherboard Settings and Configuration

Processor	CX486SX/80486SX/80486SX2/CX486DX/AM486DX/SL80486DX/80486DX/ CX486DX2/AM486DX2/SL80486DX2/80486DX2/80486DX4/P24D/Pentium Overdrive
Processor Speed	25/33/40/50(internal)/50/66(internal)/75(internal)/100(internal)MHz
Chip Set	OPTI
Max. Onboard DRAM	128MB
Cache	64/128/256/512KB
BIOS	Unidentified
Dimensions	300mm x 89mm
I/O Options	Floppy drive interface, IDE interface, parallel port, PS/2 mouse port, serial ports (2)
NPU Options	None

CONNECTIONS
Purpose	Location	Purpose	Location
IDE interface	J3	Serial port 1	J30
Parallel port	J4	Serial port 2	J31
Speaker	J6	Auxiliary keyboard connector	J32
Chassis fan power	J8	Floppy drive interface	J33
IDE interface LED	J25	PS/2 mouse interface	J35
Reset switch	J26

USER CONFIGURABLE SETTINGS
Function		Jumper	Position
	PCI type select synchronous	J9	pins 2 & 4, 3 & 5 closed
	PCI type select asynchronous	J9	pins 1 & 3, 4 & 6 closed
»	Primary IDE enabled	J14	pins 1 & 3 closed
	Primary IDE disabled	J14	pins 1 & 3 open
	Secondary IDE enabled	J14	pins 3 & 5 closed
	Secondary IDE disabled	J14	pins 3 & 5 open
»	IDE interface enabled	J14	pins 2 & 4 closed
	IDE interface disabled	J14	pins 4 & 6 closed
»	Floppy drive type select 1.44MB	J17	pins 1 & 2 closed
	Floppy drive type select 2.88MB	J17	pins 3 & 4, 5 & 6 closed
»	CPU clock frequency select 8MHz	J19	pins 1 & 2 closed
	CPU clock frequency select 16MHz (DX4 only)	J19	pins 2 & 3 closed
	PCI adapters not installed	J20	pins 1 & 2 closed
	PCI adapters installed	J20	pins 2 & 3 closed
	IDE read prefetch enabled	J22	pins 1 & 2 closed
	IDE read prefetch disabled	J22	pins 2 & 3 closed
»	Battery type select internal	J24	pins 2 & 3 closed
	CMOS memory clear	J24	pins 1 & 2 closed
»	Mouse IRQ12 enabled	J27	Closed
	Mouse IRQ12 disabled	J27	Open
»	IDE IRQ14 enabled	J28	Closed
	IDE IRQ14 disabled	J28	Open
»	Factory configured - do not alter	J29	N/A
	Password enabled	J36	Closed
	Password disabled	J36	Open

DRAM CONFIGURATION
Size	Bank 0	Bank 1	Bank 2	Bank 3
2MB	(1) 512K x 36	NONE	NONE	NONE
4MB	(1) 512K x 36	(1) 512K x 36	NONE	NONE
4MB	(1) 1M x 36	NONE	NONE	NONE
8MB	(1) 2M x 36	NONE	NONE	NONE
8MB	(1) 512K x 36	(1) 512K x 36	(1) 512K x 36	(1) 512K x 36
8MB	(1) 1M x 36	(1) 1M x 36	NONE	NONE
10MB	(1) 2M x 36	(1) 512K x 36	NONE	NONE
10MB	(1) 512K x 36	(1) 2M x 36	NONE	NONE
12MB	(1) 1M x 36	(1) 1M x 36	(1) 1M x 36	NONE
14MB	(1) 2M x 36	(1) 512K x 36	(1) 512K x 36	(1) 512K x 36
16MB	(1) 4M x 36	NONE	NONE	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
18MB	(1) 4M x 36	(1) 512K x 36	NONE	NONE
18MB	(1) 512K x 36	(1) 2M x 36	(1) 2M x 36	NONE
20MB	(1) 4M x 36	(1) 1M x 36	NONE	NONE

DRAM CONFIGURATION (CON’T)
Size	Bank 0	Bank 1	Bank 2	Bank 3
20MB	(1) 1M x 36	(1) 4M x 36	NONE	NONE
22MB	(1) 4M x 36	(1) 512K x 36	(1) 512K x 36	(1) 512K x 36
24MB	(1) 4M x 36	(1) 1M x 36	(1) 1M x 36	NONE
24MB	(1) 2M x 36	(1) 2M x 36	(1) 2M x 36	NONE
26MB	(1) 512K x 36	(1) 2M x 36	(1) 2M x 36	(1) 2M x 36
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
34MB	(1) 8M x 36	(1) 512K x 36	NONE	NONE
34MB	(1) 512K x 36	(1) 8M x 36	NONE	NONE
36MB	(1) 1M x 36	(1) 4M x 36	(1) 4M x 36	NONE
38MB	(1) 8M x 36	(1) 512K x 36	(1) 512K x 36	(1) 512K x 36
40MB	(1) 8M x 36	(1) 2M x 36	NONE	NONE
40MB	(1) 2M x 36	(1) 8M x 36	NONE	NONE
48MB	(1) 8M x 36	(1) 2M x 36	(1) 2M x 36	NONE
48MB	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36	NONE
52MB	(1) 1M x 36	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36
64MB	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36
66MB	(1) 512K x 36	(1) 8M x 36	(1) 8M x 36	NONE
72MB	(1) 2M x 36	(1) 8M x 36	(1) 8M x 36	NONE
96MB	(1) 8M x 36	(1) 8M x 36	(1) 8M x 36	NONE
98MB	(1) 512K x 36	(1) 8M x 36	(1) 8M x 36	(1) 8M x 36
104MB	(1) 2M x 36	(1) 8M x 36	(1) 8M x 36	(1) 8M x 36
128MB	(1) 8M x 36	(1) 8M x 36	(1) 8M x 36	(1) 8M x 36

CACHE CONFIGURATION
Size	Bank 0	Bank 1
64KB	(4) 8K x 8	(4) 8K x 8
128KB	(4) 32K x 8	NONE
256KB	(4) 32K x 8	(4) 32K x 8
512KB	(4) 64K x 8	(4) 64K x 8
Note: Cache is factory installed by the manufacturer and is not configurable.

CACHE JUMPER CONFIGURATION
Size	J15
64KB	Open
128KB	pins 5 & 6 closed
256KB	pins 3 & 4, 5 & 6 closed
512KB	pins 1 & 2, 3 & 4, 5 & 6 closed

CACHE JUMPER CONFIGURATION
Setting	J21
Bank 0 installed	pins 1 & 2 closed
Banks 0 & 1 installed	pins 2 & 3 closed

CPU TYPE CONFIGURATION
Type	J5
80486SX	pins 2 & 3 closed
80486DX	pins 1 & 2, 3 & 4 closed

CPU TYPE CONFIGURATION
Type	J7	J23
AMD	Open	pins 1 & 2 closed
Cyrix	pins 1 & 2, 3 & 4 closed	pins 2 & 3 closed
Intel	Open	pins 1 & 2 closed

CPU TYPE CONFIGURATION
Type	J1
80486SL-series	pins 1 & 2, 3 & 4 closed
P24T burst write	pins 5 & 6 closed
P24T write back	pins 7 & 8 closed
P24T write through	Open

CPU TYPE CONFIGURATION
Type	J18
80486SL-series	pins 2 & 4 closed
Cyrix	pins 4 & 6 closed
P24D write back	pins 3 & 5 closed
P24D write through	pins 1 & 3 closed

CPU TYPE CONFIGURATION
Type	J11
Any CPU type installed except for P24T	pins 1 & 3 closed
Pentium Overdrive	pins 3 & 5 closed
Bit 0 to stop clock	pins 2 & 4 closed
Bit 0 to stop clock	pins 4 & 6 closed

CPU SPEED CONFIGURATION
Speed	J12	J16
25MHz	pins 1 & 3, 2 & 4 closed	pins 5 & 6 closed
33MHz	pins 1 & 3, 4 & 6 closed	pins 1 & 2, 5 & 6 closed
40MHz	pins 2 & 4, 3 & 5 closed	pins 3 & 4, 5 & 6 closed
50iMHz	pins 1 & 3, 2 & 4 closed	pins 5 & 6 closed
50MHz	pins 4 & 6, 3 & 5 closed	pins 1 & 2, 3 & 4, 5 & 6 closed
66iMHz	pins 1 & 3, 4 & 6 closed	pins 1 & 2, 5 & 6 closed
75iMHz	pins 1 & 3, 2 & 4 closed	pins 5 & 6 closed
100iMHz	pins 1 & 3, 4 & 6 closed	pins 1 & 2, 5 & 6 closed

CPU SPEED CONFIGURATION (80486DX4)
Speed	J10
2x	pins 3 & 5 closed
2.5x	pins 1 & 3 closed
3x	Open
Cyrix CPU installed	pins 3 & 4 closed

IDE MODE CONFIGURATION
Speed	J13
>180ns	pins 1 & 3, 2 & 4 closed
>240ns	pins 2 & 4, 3 & 5 closed
>383ns	pins 1 & 3, 4 & 6 closed
>480ns	pins 3 & 5, 4 & 6 closed

DMA CONFIGURATION
DMA	J2
DMA 1	pins 3 & 4, 5 & 6 closed
DMA 3	pins 1 & 2, 7 & 8 closed