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How to identify low density DIMMS for iMac G3 trayloader?
Posted by: croissantking on 2025-08-30 05:03:50
Just wanted to run this past the hive mind. I want to add 2x 256MB DIMMs to my iMac G3 Rev A.

So, how do I identify low-density 256MB DIMMs? I assume they need 8 chips on each side, like this:

IMG_5830.PNGIMG_5812.PNG

Note: I do not want to use high-density 512MB modules for this even though they would technically get me to the iMac's RAM limit by being addressed at half capacity. Over on the other thread where I'm experimenting with bus clocking to 100MHz, @indibil can't get their machine to boot with 2x 512MB modules at the higher bus speed. So I'd prefer to use the correct low-density modules as part of troubleshooting (less variables to consider).
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