J-BOND COMPUTER SYSTEMS CORPORATION
486 VL450C-1
| 
 Processor  | 
 80486SX/80486DX/80486DX2  | 
| 
 Processor Speed  | 
 20/25/33/40(internal)/50(internal)/50/66(internal)MHz  | 
| 
 Chip Set  | 
 SIS  | 
| 
 Max. Onboard DRAM  | 
 32MB  | 
| 
 Cache  | 
 64/128/256KB  | 
| 
 BIOS  | 
 AMI  | 
| 
 Dimensions  | 
 230mm x 218mm  | 
| 
 I/O Options  | 
 32-bit VESA local bus slots (2)  | 
| 
 NPU Options  | 
 None  | 
| 
 CONNECTIONS  | |||
| 
 Purpose  | 
 Location  | 
 Purpose  | 
 Location  | 
| 
 External battery  | 
 J1  | 
 Turbo LED  | 
 J5  | 
| 
 Power LED & keylock  | 
 J2  | 
 Reset switch  | 
 J6  | 
| 
 Speaker  | 
 J3  | 
 32-bit VESA Local bus slots  | 
 SL1 & SL2  | 
| 
 Turbo switch  | 
 J4  | ||
| 
 USER CONFIGURABLE SETTINGS  | |||
| 
 Function  | 
 Jumper  | 
 Position  | |
| 
 »  | 
 Factory configured - do not alter  | 
 J7  | 
 Open  | 
| 
 »  | 
 A20 type select fast gate  | 
 JP2  | 
 pins 1 & 2 closed  | 
| 
 A20 type select keyboard controller gate  | 
 JP2  | 
 pins 2 & 3 closed  | |
| 
 »  | 
 CMOS memory normal operation  | 
 JP3  | 
 Open  | 
| 
 CMOS memory clear  | 
 JP3  | 
 pins 2 & 3 closed  | |
| 
 »  | 
 VESA local bus normal operation  | 
 JP27  | 
 pins 1 & 2 closed  | 
| 
 VESA local bus compatibility problems (See note below)  | 
 JP27  | 
 pins 2 & 3 closed  | |
| 
 »  | 
 PQFP CPU enabled  | 
 JSX6  | 
 Open  | 
| 
 PQFP CPU disabled  | 
 JSX6  | 
 Closed  | |
| 
 Note: If compatibility problems arise with nonstandard VESA local bus peripherals, jumper pins 2 & 3.  | |||
| 
 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  | 
| 
 20MB  | 
 (4) 1M x 9  | 
 (4) 4M 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 or (1) 32K x 8  | 
| 
 128KB  | 
 (4) 32K x 8  | 
 NONE  | 
 (1) 8K x 8 or (1) 32K x 8  | 
| 
 256KB  | 
 (4) 32K x 8  | 
 (4) 32K x 8  | 
 (1) 32K x 8  | 
| 
 CACHE JUMPER CONFIGURATION  | ||||
| 
 Size  | 
 JP4  | 
 JP5  | 
 JP6  | 
 JP7  | 
| 
 64KB  | 
 Open  | 
 Open  | 
 Open  | 
 Open  | 
| 
 128KB  | 
 Closed  | 
 pins 1 & 2 closed  | 
 Open  | 
 Closed  | 
| 
 256KB  | 
 Closed  | 
 pins 2 & 3 closed  | 
 Closed  | 
 Closed  | 
| 
 CPU TYPE CONFIGURATION  | |||||
| 
 Type  | 
 JSX1  | 
 JSX2  | 
 JSX3  | 
 JSX4  | 
 JSX5  | 
| 
 80486SX  | 
 Open  | 
 Open  | 
 Open  | 
 Closed  | 
 Open  | 
| 
 80487SX  | 
 Open  | 
 Closed  | 
 Closed  | 
 Open  | 
 Closed  | 
| 
 80486DX/DX2  | 
 Closed  | 
 Open  | 
 Closed  | 
 Open  | 
 Closed  | 
| 
 Overdrive  | 
 Open  | 
 Closed  | 
 Closed  | 
 Open  | 
 Closed  | 
| 
 CPU SPEED CONFIGURATION  | |||
| 
 Speed  | 
 JP20  | 
 JP21  | 
 JP22  | 
| 
 20MHz  | 
 Open  | 
 Open  | 
 Open  | 
| 
 25MHz  | 
 Closed  | 
 Open  | 
 Open  | 
| 
 33MHz  | 
 Closed  | 
 Closed  | 
 Closed  | 
| 
 40MHz  | 
 Closed  | 
 Closed  | 
 Open  | 
| 
 50iMHz  | 
 Closed  | 
 Open  | 
 Open  | 
| 
 50MHz  | 
 Open  | 
 Open  | 
 Closed  | 
| 
 66iMHz  | 
 Closed  | 
 Closed  | 
 Closed  | 
| 
 VESA WAIT STATE/BUS SPEED CONFIGURATION  | |||||
| 
 CPU speed  | 
 Wait states  | 
 JP8  | 
 JP9  | 
 JP10  | 
 JP11  | 
| 
 < 33MHz  | 
 0 wait states  | 
 Open  | 
 Open  | 
 Open  | 
 Open  | 
| 
 > 33MHz  | 
 1 wait state  | 
 Short  | 
 Short  | 
 Short  | 
 Short  |