LEADING TECHNOLOGY 386SX 25/33 Processor 80386SX Processor Speed 25/33MHz Chip Set Unidentified Max. Onboard DRAM 4MB Cache None BIOS Unidentified Dimensions 330mm x 218mm I/O Options Floppy drive interface, game port, IDE interface, parallel port, serial ports (2) NPU Options 80387SX [Image] CONNECTIONS Purpose Location Purpose Location Serial port 1 CN1 Reset switch J2 pin 5 Serial port 2 CN2 Ground J2 pin 8 Game port CN3 Speaker J8 Parallel port CN4 External battery J9 IDE interface LED J1 IDE interface J10 Power LED & keylock J2 pin 3 Floppy drive interface J12 Turbo switch J2 pin 4 Riser Card SL1 USER CONFIGURABLE SETTINGS Function Jumper Position » NPU disabled JP1 pins 1 & 2 closed NPU enabled JP1 pins 2 & 3 closed » External battery installed JP6 pins 1 & 2 closed External battery not installed JP6 pins 2 & 3 closed » Parity disabled (3 SIMM JP15 Open motherboard) Parity enabled (4 SIMM JP15 Closed motherboard) » Parallel port IRQ select IRQ7 JP34 pins 1 & 2 closed Parallel port IRQ select IRQ5 JP34 pins 2 & 3 closed » IDE interface enabled JP35 pins 2 & 3 closed IDE interface disabled JP35 pins 1 & 2 closed » Game port installed JP42 pins 1 & 2 closed Game port not installed JP42 pins 2 & 3 closed DRAM CONFIGURATION (WITH BANK 0A FACTORY INSTALLED) Size Bank 0a Bank 1 Bank 2 Bank 3 1MB (2) 1M x 4 NONE NONE NONE 2MB (2) 1M x 4 (1) 1M x 9 NONE NONE 4MB (2) 1M x 4 (1) 1M x 9 (1) 1M x 9 (1) 1M x 9 Note: This configuration is applicable only with Bank O factory installed. The mainboard is manufactured with either 4 SIMM banks or 3 SIMM banks and 2 DRAM banks. The 2 DRAM banks are factory installed and are not configurable. DRAM JUMPER CONFIGURATION (WITH BANK 0 FACTORY INSTALLED) Size JP11-12, JP16, JP19-27 1MB pins 2 & 3 closed 2MB pins 2 & 3 closed 4MB pins 2 & 3 closed Note: This configuration is applicable only with Bank O factory installed. DRAM CONFIGURATION (WITH BANK 0 USER INSTALLED) Size Bank 0 Bank 1 Bank 2 Bank 3 2MB (1) 1M x 9 (1) 1M x 9 NONE NONE 4MB (1) 1M x 9 (1) 1M x 9 (1) 1M x 9 (1) 1M x 9 Note: This configuration is applicable only with Bank O user installed. DRAM CONFIGURATION (WITH BANK 0 USER INSTALLED) Size JP11-12, JP16, JP19-27 2MB pins 2 & 3 closed 4MB pins 2 & 3 closed Note: This configuration is applicable only with Bank O user installed. PARALLEL PORT CONFIGURATION Parallel port JP30 JP31 LPT1 (0378h) pins 2 & 3 closed pins 1 & 2 closed LPT1 (02BCh) pins 2 & 3 closed pins 2 & 3 closed LPT2 (0278h) pins 1 & 2 closed pins 2 & 3 closed SERIAL PORT 1 CONFIGURATION Port 1 JP28 JP40 » COM 1 pins 2 & 3 closed pins 1 & 2 closed COM 3 pins 1 & 2 closed pins 2 & 3 closed COM 4 pins 2 & 3 closed pins 2 & 3 closed Disabled pins 1 & 2 closed pins 1 & 2 closed SERIAL PORT 1 INTERRUPT CONFIGURATION IRQ JP32 JP39 » IRQ4 pins 1 & 2 closed N/A IRQ3 pins 1 & 2 closed pins 1 & 2 closed SERIAL PORT 2 CONFIGURATION Port 2 JP29 JP41 » COM 2 pins 2 & 3 closed pins 1 & 2 closed COM 3 pins 2 & 3 closed pins 2 & 3 closed COM 4 pins 1 & 2 closed pins 2 & 3 closed Disabled pins 1 & 2 closed pins 1 & 2 closed SERIAL PORT 2 INTERRUPT CONFIGURATION IRQ JP32 JP39 » IRQ3 N/A pins 1 & 2 closed IRQ4 pins 2 & 3 closed pins 2 & 3 closed FLOPPY DRIVE CONFIGURATION Type JP37 JP44 A = 3.5" & B = 5.25" pins 2 & 3 closed pins 2 & 3 closed A = 5.25" & B = 3.5" pins 2 & 3 closed pins 1 & 2 closed PAGE INTERLEAVE CONFIGURATION Mode JP14 JP18 Disabled pins 1 & 2 closed pins 2 & 3 closed Enabled ( requires 4 SIMM pins 2 & 3 closed pins 2 & 3 closed configuration)