ABIT COMPUTER CORPORATION AH4 Processor 80486SX/80486DX/CX486DX2/80486DX2 Processor Speed 20/25/33/40/50(internal)/66(internal)MHz Chip Set SIS Max. Onboard DRAM128MB Cache 128/256/512KB BIOS Award Dimensions 330mm x 218mm I/O Options 32-bit VESA local bus slots (2), green PC connector NPU Options None [Image] CONNECTIONS Purpose Location Purpose Location External battery J1 Reset switch JW3 Green PC connector JP45 (pins 7 Turbo LED JW4 - 8) Power LED & keylock JW1 Turbo switch JW5 Speaker JW2 32-bit VESA local SL1 - SL3 bus slots USER CONFIGURABLE SETTINGS Function Jumper Position » Factory configured - do not J2 Open alter » CMOS memory normal operation JP16 pins 1 & 2 closed CMOS memory clear JP16 pins 2 & 3 closed » Monitor type select color JP17 Closed Monitor type select monochrome JP17 Open » Factory configured - do not JP19 Open alter » Factory configured - do not JP26 Open alter » Factory configured - do not JP30 Open alter » Factory configured - do not JP31 Open alter » Factory configured - do not JP42 Open alter DRAM CONFIGURATION Size Bank 0 Bank 1 Bank 2 Bank 3 1MB (1) 256K x NONE NONE NONE 36 2MB (1) 256K x (1) 256K x NONE NONE 36 36 2MB (1) 512K x NONE NONE NONE 36 4MB (1) 512K x (1) 512K x NONE NONE 36 36 4MB (1) 1M x 36 NONE NONE NONE 4MB (1) 256K x (1) 256K x (1) 512K x NONE 36 36 36 5MB (1) 256K x (1) 1M x 36 NONE NONE 36 6MB (1) 256K x (1) 256K x (1) 1M x 36 NONE 36 36 6MB (1) 512K x (1) 1M x 36 NONE NONE 36 8MB (1) 256K x (1) 256K x (1) 512K x (1) 1M x 36 36 36 36 8MB (1) 512K x (1) 512K x (1) 1M x 36 NONE 36 36 8MB (1) 1M x 36 (1) 1M x 36 NONE NONE 8MB (1) 2M x 36 NONE NONE NONE 10MB (1) 256K x (1) 256K x (1) 1M x 36 (1) 1M x 36 36 36 12MB (1) 512K x (1) 512K x (1) 1M x 36 (1) 1M x 36 36 36 12MB (1) 1M x 36 (1) 1M x 36 (1) 1M x 36 NONE 16MB (1) 2M x 36 (1) 2M x 36 NONE NONE 16MB (1) 1M x 36 (1) 1M x 36 (1) 1M x 36 (1) 1M x 36 16MB (1) 4M x 36 NONE NONE NONE 17MB (1) 256K x (1) 4M x 36 NONE NONE 36 18MB (1) 256K x (1) 256K x (1) 4M x 36 NONE 36 36 20MB (1) 512K x (1) 512K x (1) 4M x 36 NONE 36 36 20MB (1) 1M x 36 (1) 4M x 36 NONE NONE 24MB (1) 2M x 36 (1) 2M x 36 (1) 2M x 36 NONE 24MB (1) 512K x (1) 512K x (1) 1M x 36 (1) 4M x 36 36 36 24MB (1) 1M x 36 (1) 1M x 36 (1) 4M x 36 NONE 32MB (1) 2M x 36 (1) 2M x 36 (1) 2M x 36 (1) 2M x 36 32MB (1) 4M x 36 (1) 4M x 36 NONE NONE 32MB (1) 8M x 36 NONE NONE NONE 36MB (1) 512K x (1) 512K x (1) 4M x 36 (1) 4M x 36 36 36 36MB (1) 1M x 36 (1) 4M x 36 (1) 4M x 36 NONE DRAM CONFIGURATION (CON’T) Size Bank 0 Bank 1 Bank 2 Bank 3 36MB (1) 1M x 36 (1) 8M x 36 NONE NONE 40MB (1) 1M x 36 (1) 1M x 36 (1) 4M x 36 (1) 4M x 36 40MB (1) 1M x 36 (1) 1M x 36 (1) 8M x 36 NONE 48MB (1) 4M x 36 (1) 4M x 36 (1) 4M x 36 NONE 48MB (1) 4M x 36 (1) 8M x 36 NONE NONE 64MB (1) 4M x 36 (1) 4M x 36 (1) 4M x 36 (1) 4M x 36 64MB (1) 16M x 36 NONE NONE NONE 64MB (1) 4M x 36 (1) 4M x 36 (1) 8M x 36 NONE 64MB (1) 8M x 36 (1) 8M x 36 NONE NONE 65MB (1) 256K x (1) 16M x NONE NONE 36 36 68MB (1) 1M x 36 (1) 16M x NONE NONE 36 68MB (1) 1M x 36 (1) 8M x 36 (1) 8M x 36 NONE 72MB (1) 1M x 36 (1) 1M x 36 (1) 16M x NONE 36 72MB (1) 1M x 36 (1) 1M x 36 (1) 8M x 36 (1) 8M x 36 80MB (1) 4M x 36 (1) 16M x NONE NONE 36 80MB (1) 4M x 36 (1) 8M x 36 (1) 8M x 36 NONE 96MB (1) 4M x 36 (1) 4M x 36 (1) 16M x NONE 36 96MB (1) 4M x 36 (1) 4M x 36 (1) 8M x 36 (1) 8M x 36 96MB (1) 8M x 36 (1) 8M x 36 (1) 8M x 36 NONE 128MB (1) 16M x 36 (1) 16M x NONE NONE 36 128MB (1) 8M x 36 (1) 8M x 36 (1) 8M x 36 (1) 8M x 36 CACHE CONFIGURATION Size Bank 0 Bank 1 TAG 128KB (4) 32K x 8 NONE (1) 8K x 8 256KB (4) 32K x 8 (4) 32K x 8 (1) 32K x 8 256KB (4) 64K x 8 NONE (1) 32K x 8 512KB (4) 64K x 8 (4) 64K x 8 (1) 32K x 8 512KB (4) 128K x 8 NONE (1) 32K x 8 CACHE JUMPER CONFIGURATION Size JP1 JP2 JP4 JP40 JP41 128KB 1 & 2 1 & 2 1 & 2 1 & 2 1 & 2 256KB 2 & 3 2 & 3 1 & 2 2 & 3 2 & 3 256KB 1 & 2 2 & 3 1 & 2 1 & 2 1 & 2 512KB 2 & 3 2 & 3 2 & 3 2 & 3 2 & 3 512KB 1 & 2 2 & 3 2 & 3 1 & 2 1 & 2 Note: Pins designated should be in the closed position. CPU TYPE CONFIGURATION Type JP8 JP9 JP11 JP12 JP14 JP15 80486SX 2 & 3 Open Open 3 & 4 2 & 3 4 & 5 CX486DX 1 & 2 Closed 2 & 3 2 & 3 1 & 2, 2 & 3 3 & 4 80486DX 1 & 2 Closed 2 & 3 3 & 4 2 & 3 4 & 5 80486DX2 1 & 2 Closed 2 & 3 3 & 4 2 & 3 4 & 5 Note: Pins designated should be in the closed position. CPU TYPE CONFIGURATION (CON’T) Type JP21 JP22 JP24 JP25 JP46 80486SX 2 & 3 1 & 2 Open Open 2 & 3 CX486DX 1 & 2 2 & 3 2 & 3 2 & 3 1 & 2 80486DX 2 & 3 1 & 2 Open Open 2 & 3 80486DX2 2 & 3 1 & 2 Open Open 2 & 3 Note: Pins designated should be in the closed position. CPU SPEED CONFIGURATION Speed JP5 JP6 JP7 JP20 20MHz Closed Open Closed pins 1 & 2 closed 25MHz Closed Closed Open pins 1 & 2 closed 33MHz Open Closed Closed pins 1 & 2 closed 40MHz Closed Open Open pins 2 & 3 closed 50iMHz Closed Closed Open pins 1 & 2 closed 66iMHz Open Closed Closed pins 1 & 2 closed BUS SPEEDCONFIGURATION CPU speed JP29 <=33MHz pins 1 & 2 closed >33MHz pins 2 & 3 closed VESA WAIT STATE CONFIGURATION Wait states JP28 0 wait states pins 1 & 2 closed 1 wait state pins 2 & 3 closed