@sailor - you put information on your article that iMac has 4,5GB RAM ? is that true ?
yes, it is true.here
is specified only 2.5GB (0.5GB on motherboard + 2GB in slot).
Probably there were no 4GB memory sticks in 2005.
But if you use compatible PC2-4200 DDR2 SDRAM 4GB memory, it works (tested on OSX and linux).
I will send you exact type which I use.[ Edited by sailor 13.01.2020 - 08:33 ]
AmigaOS: Pegasos II, Sam440ep-flex, Micro A1-C, AmigaOneX1000
MorphOS: Pegasos II, Powerbook G4, iMac G5, Powermac G5 Quad