JETPRO INFOTECH COMPANY, LTD.
MB-6U(MB-450CBU)
| 
 Processor  | 
 80386DX/80486SX/80487SX/80486DX/80486DX2  | 
| 
 Processor Speed  | 
 20/25/33/40/50(internal)/50/66(internal)MHz  | 
| 
 Chip Set  | 
 UMC  | 
| 
 Max. Onboard DRAM  | 
 64MB  | 
| 
 SRAM Cache  | 
 64/256KB  | 
| 
 BIOS  | 
 AMI  | 
| 
 Dimensions  | 
 330mm x 218mm  | 
| 
 I/O Options  | 
 32-bit proprietary local bus card  | 
| 
 NPU Options  | 
 80387/3167  | 
| 
 CONNECTIONS  | |||
| 
 Purpose  | 
 Location  | 
 Purpose  | 
 Location  | 
| 
 Reset switch  | 
 J5  | 
 Power LED & keylock  | 
 J9  | 
| 
 Turbo LED  | 
 J6  | 
 External battery  | 
 J11  | 
| 
 Turbo switch  | 
 J7  | 
 32-bit proprietary local bus card  | 
 S1  | 
| 
 Speaker  | 
 J8  | ||
| 
 USER CONFIGURABLE SETTINGS  | |||
| 
 Function  | 
 Jumper  | 
 Position  | |
| » | 
 CMOS memory normal operation  | 
 W1  | 
 closed  | 
| 
 CMOS memory clear  | 
 W1  | 
 open  | |
| » | 
 Monitor type select color  | 
 W2  | 
 closed  | 
| 
 Monitor type select monochrome  | 
 W2  | 
 open  | |
| » | 
 Factory configured-do not alter  | 
 W3  | 
 open  | 
| » | 
 Tag mode select write back enabled (tag installed at U45)  | 
 W15  | 
 open  | 
| 
 Tag mode select write back disabled (tag not installed at U45)  | 
 W15  | 
 open  | |
| 
 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  | 
| 
 8MB  | 
 (4) 1M x 9  | 
 (4) 1M x 9  | 
| 
 16MB  | 
 (4) 4M x 9  | 
 NONE  | 
| 
 20MB  | 
 (4) 1M x 9  | 
 (4) 4M x 9  | 
| 
 32MB  | 
 (4) 4M x 9  | 
 (4) 4M x 9  | 
| 
 CPU JUMPER CONFIGURATION  | ||||||
| 
 Size  | 
 OSC2  | 
 W5  | 
 W10  | 
 W11  | 
 W19  | 
 W22  | 
| 
 80386DX/25  | 
 50MHz  | 
 open  | 
 N/A  | 
 N/A  | 
 open  | 
 N/A  | 
| 
 80386DX/33  | 
 66MHz  | 
 open  | 
 N/A  | 
 N/A  | 
 open  | 
 N/A  | 
| 
 80386DX/40  | 
 80MHz  | 
 open  | 
 N/A  | 
 N/A  | 
 open  | 
 N/A  | 
| 
 80486SX/20  | 
 20MHz  | 
 open  | 
 open  | 
 pins 1 & 2  | 
 closed  | 
 1 & 2 and 3 & 4  | 
| 
 80486SX/20  | 
 40MHz  | 
 open  | 
 open  | 
 pins 2 & 3  | 
 closed  | 
 1 & 2 and 3 & 4  | 
| 
 80487SX/20  | 
 20MHz  | 
 closed  | 
 pins 2 & 3  | 
 pins 1 & 2  | 
 closed  | 
 1 & 2 and 3 & 4  | 
| 
 80487SX/20  | 
 40MHz  | 
 closed  | 
 pins 2 & 3  | 
 pins 2 & 3  | 
 closed  | 
 1 & 2 and 3 & 4  | 
| 
 80486DX/25  | 
 25MHz  | 
 open  | 
 pins 1 & 2  | 
 pins 1 & 2  | 
 closed  | 
 1 & 2 and 3 & 4  | 
| 
 80486DX/25  | 
 50MHz  | 
 open  | 
 pins 1 & 2  | 
 pins 2 & 3  | 
 closed  | 
 1 & 2 and 3 & 4  | 
| 
 80486DX/33  | 
 33MHz  | 
 open  | 
 pins 1 & 2  | 
 pins 1 & 2  | 
 closed  | 
 1 & 2 and 3 & 4  | 
| 
 80486DX/33  | 
 66MHz  | 
 open  | 
 pins 1 & 2  | 
 pins 2 & 3  | 
 closed  | 
 1 & 2 and 3 & 4  | 
| 
 80486DX/50  | 
 50MHz  | 
 open  | 
 pins 1 & 2  | 
 pins 1 & 2  | 
 closed  | 
 1 & 2 and 3 & 4  | 
| 
 Note:Pins designated should be in the closed position  | ||||||
| 
 NPU JUMPER CONFIGURATION  | ||
| 
 Size  | 
 W8  | 
 W20  | 
| 
 80387  | 
 closed  | 
 closed  | 
| 
 3167  | 
 open  | 
 open  | 
| 
 SRAM JUMPER CONFIGURATION  | ||||
| 
 Jumper  | 
 32KB  | 
 64KB  | 
 128KB  | 
 256KB  | 
| 
 W12  | 
 pins 1 & 2 closed  | 
 pins 2 & 3 closed  | 
 pins 2 & 3 closed  | 
 pins 2 & 3 closed  | 
| 
 W13  | 
 pins 1 & 2 closed  | 
 pins 1 & 2 closed  | 
 pins 2 & 3 closed  | 
 pins 2 & 3 closed  | 
| 
 W14  | 
 pins 1 & 2 closed  | 
 pins 1 & 2 closed  | 
 pins 1 & 2 closed  | 
 pins 2 & 3 closed  | 
| 
 W15  | 
 open  | 
 open  | 
 open  | 
 open  | 
| 
 W17  | 
 pins 2 & 3 closed  | 
 pins 1 & 2 closed  | 
 pins 2 & 3 closed  | 
 pins 1 & 2 closed  | 
| 
 W18  | 
 N/A  | 
 N/A  | 
 pins 1 & 2 closed  | 
 pins 2 & 3 closed  | 
| 
 SRAM CONFIGURATION  | |||
| 
 Size  | 
 Cache  | 
 Locations  | 
 TAG  | 
| 
 32KB  | 
 (4) 8K x 8  | 
 Bank 0  | 
 (4) 16K x 4  | 
| 
 64KB  | 
 (8) 8K x 8  | 
 Banks 0 & 1  | 
 (4) 16K x 4  | 
| 
 128KB  | 
 (4) 32K x 8  | 
 Bank 0  | 
 (4) 16K x 4  | 
| 
 256KB  | 
 (8) 32K x 8  | 
 Banks 0 & 1  | 
 (4) 16K x 4  |