FORTRESS SYSTEMS INTERNATIONAL SPECTRUM II 486 PCI/ISA/VESA Processor CX486SX/AM486SX/80486SX/CX486DX/AM486DX/80486DX/ CX486DX2/AM486DX2/80486DX2/CX486DX4/AM486DX4/80486DX4 Processor 25/33/40/50(internal)/66(internal)/75(internal)/100(internal)MHz Speed Chip Set Unidentified Video Chip None Set Maximum 64MB Onboard Memory Maximum None Video Memory Cache 128/256/512KB BIOS AMI/Award/MR BIOS Dimensions 254mm x 218mm I/O 32-bit VESA local bus slots (2), 32-bit PCI slots (4) Options NPU None Options [Image] CONNECTIONS Purpose Location Purpose Location Turbo switch J1 Power LED & keylock J5 Turbo LED J2 32-bit PCI slots PC1 – PC4 Speaker J3 32-bit VESA local bus SL1 & SL2 slots Reset switch J4 USER CONFIGURABLE SETTINGS Function Label Position » CMOS memory normal operation JP2 Pins 1 & 2 closed CMOS memory clear JP2 Pins 2 & 3 closed » Factory configured - do not alter JP10A Open » Factory configured - do not alter JP10B Pins 1 & 2 closed » Factory configured - do not alter JP10C Pins 2 & 3 closed » Factory configured - do not alter JP10D Open » Factory configured - do not alter JP10E Open » Factory configured - do not alter JP38A Open » Factory configured - do not alter JP38B Pins 1 & 2 closed » Factory configured - do not alter JP38C Pins 2 & 3 closed IDE type select PCI IDE JP38D Closed IDE type select VESA IDE JP38D Open 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 3MB (1) 256K x (1) 512K x None None 36 36 3MB (1) 256K x (1) 256K x (1) 256K x None 36 36 36 4MB (1) 256K x (1) 256K x (1) 256K x (1) 256K x 36 36 36 36 4MB (1) 512K x (1) 512K x None None 36 36 4MB (1) 1M x 36 None None None 5MB (1) 256K x (1) 1M x 36 None None 36 5MB (1) 256K x (1) 256K x (1) 256K x (1) 512K x 36 36 36 36 6MB (1) 512K x (1) 1M x 36 None None 36 8MB (1) 1M x 36 (1) 1M x 36 None None 12MB (1) 1M x 36 (1) 1M x 36 (1) 1M x 36 None 16MB (1) 1M x 36 (1) 1M x 36 (1) 1M x 36 (1) 1M x 36 16MB (1) 2M x 36 (1) 2M x 36 None None DRAM CONFIGURATION (CON’T) Size Bank 0 Bank 1 Bank 2 Bank 3 16MB (1) 4M x 36 None None None 32MB (1) 4M x 36 (1) 4M x 36 None None 48MB (1) 4M x 36 (1) 4M x 36 (1) 4M x 36 None 64MB (1) 4M x 36 (1) 4M x 36 (1) 4M x 36 (1) 4M x 36 Note: Board accepts x 32 SIMMs. DRAM JUMPER CONFIGURATION Setting JP23 1 BK installed Pins 1 & 2 closed 2 BK installed Pins 2 & 3 closed CACHE CONFIGURATION Size Bank 0 TAG 128KB (4) 32K x 8 (1) 8K x 8 256KB (2) 64K x 32 (1) 32K x 8 512KB (4) 128K x 8 (1) 32K x 8 CACHE JUMPER CONFIGURATION Size JP20 128KB Pins 1 & 2 closed 256KB Pins 1 & 2 closed 512KB Pins 2 & 3 closed CPU SPEED SELECTION Speed JP7 JP27 JP28 25MHz Closed Pins 1 & 2 Pins 2 & 3 closed closed 33MHz Open Pins 2 & 3 Pins 1 & 2 closed closed 50iMHz Closed Pins 1 & 2 Pins 2 & 3 closed closed 66iMHz Open Pins 2 & 3 Pins 1 & 2 closed closed 75iMHz Closed Pins 1 & 2 Pins 2 & 3 closed closed 100iMHz Open Pins 2 & 3 Pins 1 & 2 closed closed CPU TYPE SELECTION Type JP11 Cyrix Pins 2 & 3 closed AMD Pins 1 & 2 closed Intel Pins 1 & 2 closed CPU TYPE SELECTION Type JP99 All CPU types Closed DX4 only Open FLASH BIOS VOLTAGE SELECTION Voltage JP12 JP80 5v Pins 1 & 2 closed Pins 1 & 3, 2 & 4 closed 12v Pins 2 & 3 closed Pins 3 & 5, 4 & 6 closed