Yay! RAM issue solved with G4 MDD!

I'm so relieved.
Just bought my first Mac, and I thought it was a dud. Would only recognize 512 of RAM, even though I had 2 gigs installed.

Turns out the suggestions here were absolutely correct. Yes, Apple computers *are* picky about the memory you put in them.

I ordered PC3200 RAM from a dealer on eBay, assuming that it was backwards compatible (since everywhere you read says it will work in computers with PC2700 or PC2100, and just operate at the lower bus speeds.)

So after worrying remendously that the computer was defective, I got the replacement RAM (PC2700) today. Popped it in, and voila! Computer sees the full two gigs.

Thanks again for all the suggestions. I've certainly learned a lot from the gang on here already.

So if anyone's wondering, feel free to learn from my experience! Macs are tempermental when it comes to RAM, so make sure you buy EXACT SPEC memory, and preferabbly from a noteworthy Mac memory dealer.

Odd. I find it unlikely that it was the mac being fickle that was at fault here. I suspect you either had bad chips or just plain bought cheap RAM.

PC3200 is backwards compatible with 2700. However, some cheap PC3200-particularly the first sticks that came out at a fairly low price point-required higher-than-standard voltages to operate even BELOW 200MHz, and had very, very loose timings. Throw that kind of RAM in a Mac and it may very well have a fit... most PCs will too. I've dumped all kinds of "non-Apple" RAM into my Macs and never had a problem.

As long as you buy *quality* RAM that meets or exceeds all of the computer's requirements, it really shouldn't matter for any system that takes DDR, DDR2, DDR3 (no Macs use this yet) or FB-DIMMs. SDRAM is another story... then you do get into issues with compatibility due to memory density.

Well, I'm not sure if it was the RAM being faulty. Only one of the DIMM slots was "working" regardless of which RAM stick I put in. I tried all types of combinations with the same result.

Here's the previous thread (ad nasuem! )

http://www.mac-forums.com/forums/showthread.php?t=80608

Geeky1 said:

Odd. I find it unlikely that it was the mac being fickle that was at fault here. I suspect you either had bad chips or just plain bought cheap RAM.

PC3200 is backwards compatible with 2700. However, some cheap PC3200-particularly the first sticks that came out at a fairly low price point-required higher-than-standard voltages to operate even BELOW 200MHz, and had very, very loose timings. Throw that kind of RAM in a Mac and it may very well have a fit... most PCs will too. I've dumped all kinds of "non-Apple" RAM into my Macs and never had a problem.

As long as you buy *quality* RAM that meets or exceeds all of the computer's requirements, it really shouldn't matter for any system that takes DDR, DDR2, DDR3 (no Macs use this yet) or FB-DIMMs. SDRAM is another story... then you do get into issues with compatibility due to memory density.

Click to expand...

There have been many reports of correctly specced RAM that passed memtest86 with flying colors causing kernel panics when put into certain Macs. It's just an unexplainable (but repeatable) fact.