Single Rank Vs Dual Rank. Dual rank is a bit like dual channel in that interleaving (on module in the case of dual rank) can boost performance, although dual rank is not as efficient as dual channel, since the data bus is shared between ranks. Don't worry about single vs. dual rank; and in any event you shouldn't mix them.
This is due to abstraction on the part of the LRDIMM buffer. Don't worry about single vs. dual rank; and in any event you shouldn't mix them. You may want to pull the existing DIMMS out of your iMac to see what they are.
The actual thru put is comparable to how many mhz single rank at same cas latency?
The number before the "R" indicates whether it is single or dual rank.
Single rank vs dual rank: which is more suitable for laptop? When it comes to the memory kits we wanted to test with just two and then all four DIMM slots populated and we also needed to test with single-rank and dual-rank memory modules. Dual Rank Memory is basically like having two Single Rank chip ranks on one memory module, with only one rank accessible at a time.