The Apple official stance on RAM for the iMac 8.1 model is that 2 2-MB RAM [chips] is the max. Original has 2 1-MB. Other internet comments noted that a 2-MB and 4-MB for 6-MB total was possible for the system to recognize.
Does going the extra 2-MB for a total of 6 provide much advantage than sticking to the official 4-MB?
My interest in updating the RAM is to provide a better base for the new op-sys available (Yosemite). Since Yosemite was the Nov. 2014 subject at SWAG ... is there any different status for the upgrade?
President Emeritus Dave Weston responds:
The iMac in question appears to be a 24” (early 2008) model, and according to the place I get my memory from, Data Memory Systems, this machine has been tested, and works with up to 6GB of RAM (1x4GB and 1x2GB). I’ve used this source for years and trust them entirely.
More RAM is, in my opinion, always better. You won’t see a tremendous performance boost, but you should be able to run Yosemite without difficulty. Maximizing the RAM is about all you can do with this machine, short of considering a newer one.