Originally Posted by marklovesportland
When some of you write than some memory is "better" than others, exactly what does that mean? Does non-Apple memory work properly, or does it NOT?
Depends. Apple RAM is just the same RAM you get from everywhere else. Usually the only real difference between "good" RAM and "bad" RAM is that one brand actually tests their chips before they send them out the door. So as long as you buy decent quality RAM, it shouldn't matter what brand it is, it will work in a Mac just fine.
However, I have also seen on occasion cheap RAM chips that will work fine if they're the only chip in a machine, but when paired with other cheap memory one of the two chips either won't register at all, or will register only some of the total RAM on the chip.
Again, you get what you pay for. Paying more for RAM though usually just means that someone else has already tested it for you, and you're getting a good chip. (usually)