I wouldn't reccomend EDO.
EDO = Extended Data Out, this means data is stored longer than FPM
ready for the CPU to pick up a 2nd time.
This is not how an expert would explain it but I'm giving my own
understanding of it.
I think the difference in technology creates problems for older
machines, most notably Apple Macs (a few of which have been known to
be damaged by EDO in particular).
I've heard from a few people that they would never use EDO again on
their Phase5 Blizzard accelerators which often date to the mid-90's.
What hope then does an A4000 have of 100% reliable performance using
EDO designed for P75->P120 machines?
The newer EDO is more incompatible still and some DCE hardware such as
the CD32's SX32-Pro actually supported it, albeit with a special
jumper to notify the accelerator of a 50ns timing.
EDO is a lot more common but I would chose FPM every time. The best
type of memory for Amiga in my opinion is single-sided FPM, 2k/4k
refresh and non-composite (made up of as little DRAM chips as
possible).
:-)
