>>> What are EDO DIMMs and what makes them better? If they're so good then, why is Apple lagging behind? I know PC clone maker have been using EDO memory for a while now, but I don't know enough about EDO memory to make a comparison with Mac memory. <<<
EDO stands for Extended Data Out. What that means is that it's got added circuitry so that reading can take place while a refresh of the memory is taking place. With regular memory, there's a 1 cycle wait state if you read from the memory while it's being refreshed, but this doesn't happen with EDO memory.
EDO is slightly more expensive, but it can help avoid the need for a L2 cache, and even provide a slight speed boost when you have a level 2 cache. The figure generally quoted is a 15% speed increase, but if you're hitting the cache you won't have much of a benefit.
