Installing an
MMX OverDrive Processor
    As far as ease of installation the simplest way to upgrade the CPU on a 2144, 2168, 2134, 2176 or 2159-Sxx Aptiva is via an MMX OverDrive unit, a very simple drop-in install.

    The two primary options in the past as far as MMX OverDrive CPUs are the Intel Pentium OverDrive Processor and the Evergreen Technologies MxPro featuring the WinChip, however several others have recently joined the field of options, including the Powerleap PL-ProMMX-233 and Kingston TurboChip, both based on Intel Pentium CPUs.

    For an in depth discussion of these and various other CPU upgrade options click here.

    To upgrade with the Intel unit one must have a motherboard with a "Socket 7" processor socket, the Evergreen MxPro can be installed on systems with both Socket 5 and Socket 7 configurations.

    In order to determine what the upgrade options are for your particular model Aptiva I suggest you check my Intel MMX page for your model. Any systems which will support the Intel upgrade (Socket 7 systems) can optionally install the Exergreen MxPro. If your model is not listed on the Intel page you likely have Socket 5 and the Evergreen unit will be your only option.

    The primary issue to note with CPU upgrades on the early Pentium Aptiva systems is the infamous Post 127 error. While this error at startup does not impact the system functionality it is an annoyance that has to be dealt with every time the PC is started. There is a rather large "Post 127 Club" out there of Aptiva owners as this is the cost of upgrading past 166MHz on Axx and Mxx systems and past 200MHz on Cxx and 2159-Sxx systems.


    Diagram of a Socket 7-style CPU assembly
    1. Unplug your Aptiva and remove the cover

    2. Locate the CPU socket on the motherboard

    3. Press gently down on the heat sink retaining clip until it pops out of it's groove

    4. Remove the clip

    5. To remove the CPU itself locate the release lever and lift it into an upright position

      If the heat sink is overlapping the release lever gently slide it away NOTE: On my 2176-C66 the ZIF (Zero Insertion Force) lever was obstructed by the heat sink. If you find that the heat sink is overlapping the release lever gently slide it over out of the way.

    6. When the release lever is fully upright lift the processor out of the socket

      line up the notch on the OverDrive Processor with the notch on the CPU
    7. Taking care not to bend any of the pins on the OverDrive Processor, line the unit up over the socket making sure that the notch on the socket lines up with the notch on the processor [IMAGE]

    8. When the processor is positioned in the socket lower the ZIF lever until it locks in place in a horizontal position [IMAGE]

      NOTE: On certain systems if the bus speed is less than 66MHz, you may also have to change a few motherboard jumper settings during the processor installation.

      Evergreen provides a table that tells you which scenarios require a jumper change, and your hardware guide (or the online IBM Aptiva Hardware Manuals) can tell you which jumpers to change.

    9. Replace the cover on your PC and power your system up. In the case of the Evergreen upgrade start your system with the bootable diskette provided.


    JP2 Jumper settings
      Although the motherboard on Mxx, Axx, Cxx and Sxx Aptivas supports a bus speed of 66.66MHz the speed is set from the factory at 60MHz. To get the full benefit from a 200MHz CPU you may want to change the jumper settings to set your bus speed to 66.66MHz. This is a very simple and safe procedure.

      The illustration at the left identifies the location of jumper block JP2 which is where you will make this change. You will likely find the two jumpers set from the factory on pins 3+5 and 4+6, just remove each jumper and replace them so that they cover 1+3 and 2+4. Voila, 66.66MHz!

      THe above illustration reflects the motherboard found on a 2176-Cxx Aptiva with the ATI 3D Rage graphics chip. For details on other Aptiva models see the appropriate pages in the Aptiva Online Service Manuals.


    Intel Pentium OverDrive

    Evergreen MxPro OverDrive

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    DON5408's Unofficial IBM Aptiva™ Support Site
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