Intel Above Board MC

@70D1.ADF Intel Above Board MC

ABMC.exe Operating Software Diskette (303989-001, 20 May 1991) [P] (zipped image)
Readme for ABMC.exe

Intel Above Board MC Installation Guide (scan by David Beem)

Intel Above Board Support Pages (archived)
Intel Above Board - Installation Problems and Solutions

Above Board MC
Installing Memory
SIMM Compatibility
I/O Daughterboard

Above Board MC [P] [P]

1-8 30-pin SIMM sockets
J1 50-pin header for I/O board
U8,14 Dallas DS1005C-003 Delay Line
U11 pads for 8-pin DIP (switch, socket?)
U16 Xilinx XC3342 PQ100C-5014
U17,18,22,26 MT5C6404DJ-15 16Kx4 SRAM
U35 M5M28C64AFP-15 8Kx8 EEPROM

Installing Memory

256 KB, 1 MB and 4 MB SIMMs are supported. All installed SIMMs must be of the same size and 100 ns or faster. 85 ns or faster SIMMs allow for zero wait state operation.

Restrictions depending on the type of the slot in which the adapter is installed:

16-bit Slot

  • Maximum extended memory: 16 MB
  • Maximum expanded memory: 32 MB
  • You must add SIMMs two at a time.
  • Any extra memory on an Above Board above 16 MB of extended memory can be set up as expanded memory.

32-bit Slot

  • Maximum extended memory: 64 MB
  • Maximum expanded memory: 32 MB
  • You may add SIMMs two at a time up to 16 MB of total extended memory (all boards in your system), but your board will operate faster if you install the SIMMs four at a time.
  • Beyond 16 MB of extended memory, SIMMs must be added four at a time, for all boards in your computer.
  • Any Above Board that is supplying extended memory above 16 MB must be placed in a 32-bit slot.

SIMM Compatibility

Source: SIMMs for the Above Board MC

The following table lists the SIMMs that Intel has verified are compatible with the Above Board MC. The table lists both the part number on the module ("bottom side" of the module) and the part number on the DRAMs ("topside" of the module).

You cannot mix different-sized modules (256 KB, 1 MB, 4 MB) on the same Above Board MC. You must use at least 100 ns RAM. Using 85ns or faster, you can run the Above Board MC at 0 wait states for optimum performance.

ManufacturerModule Part Number
("Bottom side")
DRAM Part Number
256 KBMicron Tech.MT9259M-xxMT1259EJ-xx
FujitsuMB85227-xx MB85240-xx
Texas InstrTM4256GU9-xxTMS4256FML-xx
1 MBMicron TechMT8C9024M-xxMT4C1024-xx
MitsubishiMH1M09AOJ-xx MH1M09AOJ-xxM5M41000AJ-xx M5M41000BJ-xx
Oki *MSC2312A-xxYS9MSM511000AJS-xx
Texas Instr.TX024EAD9-xxTMS4C1024DJ-xx
ToshibaTHM91000S-xx THM91000AS-xx THM91000AS-xxTC511000J-xx TC511000AJ-xx TC51000AJ-xx
4 MBNECMC-424100A9B-xxUPD424100LA-xx

* We have seen some Oki SIMMs that are a millimeter shorter than the SIMM sockets on the Above Board MC. If you are experiencing problems with these SIMMs, verify they are seated correctly. If they appear too small to fit snugly, replace with new SIMMs.

Note: IBM SIMMs are incompatible with Above Boards.

I/O Daughterboard

Connects to the 50-pin header (J1) and provides 1x serial and 1x parallel port. Includes a replacement MCA bracket for the adapter. Sold separately.

Content created and/or collected by:
Louis Ohland, Peter Wendt, David Beem, William Walsh, Tatsuo Sunagawa, Jim Shorney, Tim Clarke, Kevin Bowling, Tomáš Slavotínek, and many others.

Ardent Tool of Capitalism - MAD Edition! is maintained by Tomáš Slavotínek.
Last update: 30 Jul 2023 - Changelog | Legal Info & Contact