I have two iBooks (G3/700 and a G3/600, both 12"). I want to upgrade the RAM in each. (Both came with 128MB built in). I got a 512MB module and a 256MB module. For some reason, the G3/700 doesn't seem to recognize the RAM. I tried both modules in the G3/700 and neither were recognized. (I put them in and out several times to make sure that they were in correctly.) I tried both in the G3/600 and they both worked. I imagine that this probably indicates some sort of hardware problem with the G3/700. Is there anything else I can try, though? The G3/700 is working fine and I've run TechTool Pro and everything checks out fine. I don't know if this makes a difference, but I noticed that according to the specs these iBooks take PC100 RAM modules. The ones I got were PC133. I got them from Coast to Coast Memory (18004MEMORY). I tried both OS 9 and OS X and got the same results. Any help would be appreciated.