COMPUTREND SYSTEMS, INC.

UMC-386 (MS-3131 Ver. 1.1)

Processor	80386DX
Processor Speed	33/40MHz
Chip Set	UMC
Max. Onboard DRAM	32MB
SRAM Cache	32/64/128/256KB
BIOS	AMI
Dimensions	220mm x 220mm
I/O Options	Auxiliary keyboard connector
NPU Options	80387

CONNECTIONS
Purpose	Location	Purpose	Location
External battery	J1	Turbo switch	J2/15 - 17
Power LED & keylock	J2/1 - 5	Turbo LED	J2/12 & 13
Speaker	J2/7 - 10	Auxiliary keyboard	KB2
Reset switch	J2/19 & 20

USER CONFIGURABLE SETTINGS
Function		Jumper	Position
»	Monitor type select monochrome	JP1	open
	Monitor type select color	JP1	closed
»	NPU disabled	JP3 JP9	open open
	NPU endabled	JP3 JP9	closed closed
»	Battery select internal	J1	pins 2 & 3 closed
	battery select external	J1	connected

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
8MB	(4) 1M x 9	(4) 1M x 9
16MB	(4) 4M x 9	NONE
32MB	(4) 4M x 9	(4) 4M x 9

CACHE JUMPER CONFIGURATION
Size	JP4	JP5	JP6	JP7	JP8	JP11	JP12	JP13
32KB	open	open	pins 2 & 3	pins 1 & 2	pins 1 & 2	pins 2 & 3	pins 1 & 2	open
64KB	open	open	pins 2 & 3	pins 1 & 2	pins 1 & 2	pins 1 & 2	pins 2 & 3	closed
128KB	closed	open	pins 1 & 2	pins 2 & 3	pins 1 & 2	pins 1 & 2	pins 2 & 3	closed
256KB	closed	closed	pins 2 & 3	pins 2 & 3	pins 2 & 3	pins 1 & 2	pins 2 & 3	closed
Note:Pins designated should be in the closed position.

CACHE CONFIGURATION
Size	Cache SRAM	Location	TAG
32KB	(4) 8K x 8	Bank 0	(1) 8K x 8
64KB	(8) 8K x 8	Banks 0 & 1	(1) 8K x 8
128KB	(4) 32K x 8	Bank 0	(1) 8K x 8
256KB	(8) 32K x 8	Banks 0 & 1	(1) 32K x 8

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UMC-386 (MS-3131 Ver. 1.1), motherboard, processor, socket, pentium, pentium pro, celeron, powerpc, alpha, 8088, 8086, 286, 386, 486, configuration, RAM, DRAM, floppy, jumper, connections