DDR3 Server Memory: Why are some module builds much less costly than others? Let’s say you are looking at prices for 4GB DDR3 Registered DIMMs for servers. You see a 4GB Dual Rank (e.g., KTH-PL313/4G), and another 4GB Dual Rank (KTH-PL3138/4G) alternative, and one of November 8, 2016 News