Maximum RAM issue


macrumors regular
Original poster
Jan 24, 2002
Hi folks...

I just upgraded the RAM in my g4/466/jaguar, and I have a question about it.

I have 3 slots for ram, and they are full. After upgrading my ram I went to system profiler to make sure it was recognized, and sure enough it was. So far, great.

I also noticed in profiler that I have a mysterious 4th slot which is empty. I say mysterious because I don't know where it is. The three that I know of are all in a row with their little clips for securing the ram, but I don't see anything similar anywhere else. As I'm not a real hardware guy I am wondering if I am missing something or of profiler is hallucinating this 4th slot.

Additionally, a friend with a dual 450 g4 recently told me his mac has 4 slots but will only recognize three of them; loading the 4th causes him all sorts of problems. So, if in fact I do have this 4th slot somewhere, an I inviting trouble by using it? I have extra ram laying around that I'd love to put to work for me.



Moderator emeritus
Mar 25, 2002
London, England
My old PowerMac G4 400Mhz AGP certainly had 4 DIMM slots all next to one-another, so I realy would have thought your G4 466Mhz (of the same generation I would think) would only have 3 :confused:


macrumors 68020
Dec 3, 2001
The models with 466, 533, 667, 733, 800, 867, 933Mhz and dual 1Ghz cpus, not including the newest "mirrored doors" G4s all have 3 ram slots, PC133 memory, a 4th PCI slot and 4 x AGP.

The models with 350, 400 and 500Mhz cpus have 4 ram slots, PC100 memory, 3 PCI slots and 2 x AGP.

I guess the system profiler is ignorant to the design change in the digital audio G4s and above so it still thinks there's 4 RAM slots or something.

With 512Mb DIMMs being so dirt cheap these days I can't see how being limited to 1.5Gb is a problem, I can't wait to get a more recent mac model so I can max out to 1.5Gb for under £120.