Also, SDRAM and EDO are totally different configurations. SDRAM is 168 pin "DIMM", and EDO is a 72 pin "SIMM". Therefore it won't fit the same slot/socket.
Not sure, but I believe some very early DIMM motherboards had SIMMs to allow mixing of RAM types, and generally RAM has to be paired in like quantities i.e. 32MB with 32MB for best performance.
The other thing is to look for "fast RAM" in terms of latency. On the other hand, I doubt there is any noticeable perfomance increase between CAS2 and CAS3 RAM. (Unless you benchmark video frame rates and gain 1 or 2
Hope the water isn't too muddied now!
RGDS