This document is for the baby-sized (13.3" x 8.5") 80486DX-33, DX2/66, DX-50, and 80486SX-25 EISA motherboard. The part number for this board is 09-00159-xx. It's identifying features are: an LED between expansion slots #5 and #6; eight 32-bit expansion slots; four sockets for SIMMs (four banks); a ZIF socket for any DX, DX2, SX & Intel P24T Overdrive. The First 6 EISA slots support Bus Mastering Controllers. The Standard EISA bus clock is fixed at 8.3MHz. +=============================+ + + + MEMORY CHART + + + + + +=============================+ The following chart shows all of the possible memory configurations ============================ Memory Banks ---------------------------- MB 0 1 2 3 ---- ---- ---- ---- ---- 4MB 1MB 8MB 1MB 1MB 12MB 1MB 1MB 1MB 16MB 1MB 1MB 1MB 1MB 16MB 4MB 20MB 1MB 4MB 24MB 1MB 1MB 4MB 32MB 4MB 4MB 36MB 1MB 4MB 4MB 40MB 1MB 1MB 4MB 4MB 48MB 4MB 4MB 4MB 52MB 1MB 4MB 4MB 4MB 64MB 4MB 4MB 4MB 4MB In the table above 70ns or 60ns access time for DRAM /SIMMs is required, 1MB indicates that a 1Mx36 SIMM is installed in the bank, and 4MB indicates that a 4Mx36 SIMMs are installed in the bank. (1Mx36) = 4MB / 4096Kb of RAM and (4Mx36) = 16MB / 15360Kb of RAM Micronics Computers has tested and verified the following memory brands: Toshiba, Siemens, Mitsubishi, NEC & Micron +=============================+ + + + MOTHERBOARD JUMPER SETTINGS + + + +=============================+ J23 Keyboard connector Pin 1 - Keyboard clock Pin 2 - Keyboard data Pin 3 - no connector Pin 4 - Ground Pin 5 - +5 volts DC J3 External 6-volt battery connector Pin 1 - Battery Positive Pin 2 - no connector Pin 3 - Ground Pin 4 - Ground J13 External speaker Pin 1 - Speaker Pin 2 - no connector Pin 3 - Ground Pin 4 - +5 volts DC J11 Keylock / Power LED Pin 1 - Power LED signal Pin 2 - no connector Pin 3 - Ground Pin 4 - Keyboard lock signal Pin 5 - Ground J9 Reset switch Pin 1 - Signal Pin 2 - Ground J8 Turbo switch Pin 1 - Signal Pin 2 - Ground J5 Turbo LED Pin 1 - Signal Pin 2 - Ground J12 Video mode Color - INSTALLED {Default} MONO - OPEN CPU SELECTION i486SX ZIF Socket PQFP Surface mounted CPU Selection JP1 JP2 JP3 None i486SX 1-2 3-4 2-3 None i486DX or I486DX2 2-3 1-2 1-2 & 3-4 i486SX NONE 1-2 3-4 2-3 i486SX i486DX OR DX/2 2-3 1-2 1-2 & 3-4 i486SX i487SX 1-2 1-2 1-2 & 3-4 i486SX i486SX Overdrive 1-2 2-3 1-2 & 3-4 For Earlier Revisions Ax J6 i486SX 2-3 i486DX 1-2 & 3-4 CPU Clock Speed J7 J10 33Mhz OFF ON i486DX/33, DX2/66, SX/33 25Mhz ON ON i486SX/25, DX2/50 50Mhz OFF OFF i486DX/50 Cache configuration =================== Cache J15 J16 J17 J18 J19 J20 J21 J22 ---------------------------- 64K 1-2 1-2 1-2 1-2 1-2 1-2 2-3 3-4 (8) 8Kx8 -20ns SRAM for U110-U116 & U118 (1) 64Kx1 -20ns SRAM for U103 (1) 32Kx8 -20NS SRAM for U104 128K 2-3 1-2 1-2 2-3 1-2 1-2 1-2 4-5 (4) 32Kx8 -20ns SRAM for U110-U112 & U118 (1) 64Kx1 -20ns SRAM for U103 (1) 32Kx8 -20NS SRAM for U104 256K 2-3 2-3 1-2 1-2 1-2 1-2 1-2 1-2 (8) 32Kx8 -20ns SRAM for U110-U116 & U118 (1) 64Kx1 -20ns SRAM for U103 (1) 16Kx4 -20NS SRAM for U101 & U102 512K 2-3 2-3 2-3 2-3 2-3 2-3 1-2 4-5 (4) 128Kx8 -20ns SRAM for U105-U108 (1) 64Kx1 -20ns SRAM for U103 (1) 32Kx8 -20ns SRAM for U104 U101 & U102 SRAM must be removed from a 256k cache configuration.