| Issue 1: 128MB DIMMs are typically composed of 16 chips, each a 16Mx4 part. There are two types that are used, the "4K Refresh" and the "8K Refresh". The Crescendo/7200 is not compatible with some DIMMs made with "8K Refresh" parts because the timing margins are so thin that the electrical \u8218\u196\u250 noise\u8218\u196\u249 generated by the card causes errors. The "8K" versus "4K" parts can be identified by the part numbers of the chips on the DIMM, or by checking with the manufacturer of the chips.
One solutions is to contact the chip vendor/manufacturer and have the chips replaced with DIMMs that are built with "4K Refresh" parts. 4K Refresh DIMMs are considerably more prevalent, but users are advised to ask before purchasing.
Issue 2: The 128MB DIMMs do meet compatibility, however, you are running an older version of the 7200 enabler.
After checking and verifying that the 128MB DIMMs that are installed on either the logic board or the card are made with "4K Refresh" parts and not "8K Refresh", check to see which version of the 7200 enabler you are running. This can be found in the System folder of your Operating System hard drive. If you are not running version 1.1 or later, you will need to update. With the release of the 7200 enabler, Sonnet expands its support of RAM running on both the upgrade card and the logic board. To update to version 1.1, remove the 7200 processor upgrade and boot the computer. Then download the Crescendo/7200 software. Once downloaded, run through the installation. The installer will remove any old version of the enabler that is currently installed and install version 1.1. When the installer is done, shut the computer down, reinsert the 7200 upgrade processor, and boot the computer normally. |