IBM Mono/Color  (250-0300/01)     Memory Upgrades      Faxback Doc. # 3283

The memory expansion port allows you to upgrade the memory size of your
computer by installing a single inline memory module (SIMM) into this
socket.  You can install a 4MB, 8MB, or 16MB, SIMM into your computer.

When you are purchasing your memory expansion, make sure that it meets the
following criteria and is compatible with the IBM part numbers listed:

    72-pin, low-power, SIMM form factor

*   60, 70, or 80 nanoseconds (ns) per row access time

    Fast page mode operation

    Slow refresh capability-125 microseconds per row address

      - for 4MB, 1024 cycles per 128 milliseconds

      - for 8MB or 16MB, 2048 cycles per 256 milliseconds

MB         Organization            IBM Part Number

4          1 Mbit x 36             79F1000

8          2 Mbit x 36             60G0378

16         4 Mbit x 36             60G0379

Warning:  SIMMs are sensitive to static electricity.

      *   80 nanoseconds will give you the best possible performance.

To add a SIMM, complete the following steps:

1.  Save any files you are working with.

2.  Slide the power switch 1 to Off O.

3.  Disconnect all external device cables.

4.  Close the connector door.

5.  Close the lid.

6.  Turn the computer over so that the feet are facing up and the
    connector door is toward you.

7.  Remove the battery pack door and the battery pack.

8.  Using the picture, locate and remove the accessory door using a key or
    coin.  Be careful not to pull the battery cables loose.

Warning:  Be careful not to drop anything inside your computer.  Serious
          damage to the internal components could result.

9.  Locate the memory expansion socket inside the accessory compartment.

10. Locate the notch 1 on the SIMM.

11. With the notch facing as shown 1, insert the SIMM card into the socket
    at an angle.  Then, push the card down firmly until it locks into
    place.

12. Replace the accessory door.  If you have a modem installed, place the
    batteries between the SIMM and the modem with the cables under the
    modem and the velcro facing up before replacing the door.  The velcro
    will connect with the battery when the door is replaced.

13. Reinstall the battery pack.

14. Restart the computer.

Removing a SIMM

Warning:  SIMMs are sensitive to static electricity.

To remove an already installed SIMM, complete the following steps:

1.  Save any files you are working with.

2.  Slide the power switch to Off O and disconnect all external devices.

3.  Turn the computer over so that the feet are facing up.

4.  Remove the battery pack door and the battery pack.

5.  Open the accessory door using a key or coin.

Warning:  Be careful not to drop anything inside your computer.
          Serious damage to the internal components could result.

Note:  Remember how the SIMM is positioned for replacement.

6.  Pull back the two clips and remove the SIMM card.

7.  Replace the accessory door.

8.  Replace the battery pack and battery pack door.


(br/all-11/3/94)