MB-1425/33/40/50UCV-A Motherboard Settings and Configuration

Processor	CX486S/80486SX/80487SX/80486DX/ODP486SX/80486DX2/ Pentium Overdrive
Processor Speed	25/33/40/50(internal)/50/66(internal)MHz
Chip Set	Biostar
Max. Onboard DRAM	64MB
Cache	32/64/128/256KB
BIOS	AMI
Dimensions	330mm x 218mm
I/O Options	32-bit VESA local bus slots (3)
NPU Options	None

CONNECTIONS
Purpose	Location	Purpose	Location
External battery	JP8	Power LED & keylock	JP15E
5V ground	JP15A	Speaker	JP15F
Turbo switch	JP15B	32-bit VESA Local bus slot	V1
Reset switch	JP15C	32-bit VESA Local bus slot	V2
Turbo LED	JP15D	32-bit VESA Local bus slot	V3

USER CONFIGURABLE SETTINGS
Function		Jumper	Position
»	CMOS memory normal operation	JP8	pins 2 & 3 closed
	CMOS memory clear	JP8	pins 3 & 4 closed
»	Power good signal detect from power supply	JP11	pins 1 & 2 closed
	Power good signal detect from board	JP11	pins 2 & 3 closed
»	One CPU (PQFP or PGA) on board installed	JP12	pins 1 & 2 closed
	Two CPUs (enabled PGA and disabled PQFP) on board installed	JP12	pins 2 & 3 closed
»	Monitor type select color	JP14	pins 2 & 3 closed
	Monitor type select monochrome	JP14	pins 1 & 2 closed
»	Add on card select normal operation	JP28	pins 1 & 2 closed
	Add on card select Weitek 9000 VGA card installed	JP28	pins 2 & 3 closed

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) 1M x 9	(4) 256K x 9
8MB	(4) 1M x 9	(4) 1M x 9
16MB	(4) 4M x 9	(4) 4M x 9
17MB	(4) 4M x 9	(4) 256K x 9
20MB	(4) 4M x 9	(4) 1M x 9
32MB	(4) 4M x 9	(4) 4M x 9
64MB	(4) 16M x 9	NONE

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

CACHE JUMPER CONFIGURATION
Size	JP5	JP6	JP7	JP9	JP10
32KB	pins 2 & 3	Open	Open	Open	Open
64KB	pins 1 & 2	Open	Open	Closed	Open
128KB	pins 2 & 3	pins 2 & 3	Closed	Closed	Open
256KB	pins 1 & 2	pins 1 & 2	Closed	Closed	pins 2 & 3
256KB	pins 1 & 2	pins 1 & 2	Closed	Closed	pins 1 & 2
Note:Pins designated should be in the closed position.

CPU TYPE CONFIGURATION
Type	JP16	JP17
CX486S	Open	pins 2 & 3 closed
80486SX	Open	pins 2 & 3 closed
80487SX	pins 2 & 3 closed	pins 1 & 2 and 3 & 4 closed
80486DX	pins 1 & 2 closed	pins 1 & 2 and 3 & 4 closed
ODP486SX	pins 2 & 3 closed	pins 1 & 2 and 3 & 4 closed
80486DX2	pins 1 & 2 closed	pins 1 & 2 and 3 & 4 closed
Pentium Overdrive	pins 1 & 2 closed	pins 1 & 2 and 3 & 4 closed

CPU SPEED CONFIGURATION
Speed	JP21	JP22	JP23	JP27
25MHz	Closed	Open	Closed	Open
33MHz	Closed	Closed	Open	Open
40MHz	Open	Open	Closed	Closed
50i MHz	Closed	Open	Closed	Open
50MHz	Open	Closed	Open	Closed
66i MHz	Closed	Closed	Open	Open

VESA BUS SPEED CONFIGURATION
Mode	JP19	JP20	JP25 (V2)	JP26 (V1)	JP29 (V3)	JP30 (V2 & V3)
Synchronous	pins 1 & 2	pins 1 & 2	pins 1 & 2	pins 1 & 2	pins 1 & 2	pins 1 & 2
Asynchronous	pins 2 & 3	pins 2 & 3	pins 2 & 3	pins 2 & 3	pins 2 & 3	pins 2 & 3
Note:Pins designated should be in the closed position. When V2 & V3 are used at the same time, JP25 must be left open.