AMD A-Series "Kaveri" Performs Better with Dual-Rank DIMMs
 

AMD's A-Series "Kaveri" APUs perform tangibly better on system with dual-rank memory modules, according to an investigative report by ComputerBase.de. According to the report, the chip yields its best memory bandwidth when both its memory channels are populated with 2-rank DIMMs each. Either that, or four modules with one rank each. The report also found out that Kaveri can take advantage of DDR3-2400 as advertised. There was a 15.2 percent jump in performance between DDR3-1866 and DDR3-2400.

An unreliable way of checking whether a DIMM has two ranks is by looking at whether both sides of its PCB has DRAM chips; a reliable way of doing that, however, is using software such as AIDA64 (MotherboardSPD tab), which lists out number of ranks, and number of banks per rank; and of course, looking up the specs sheet. The reason visual inspection of a DIMM is not reliable these days is because of the way modern DRAM chips are designed. There are instances of DIMMs with chips on just one side, yet 2 ranks. Find more performance numbers at the source.

http://www.techpowerup.com/197145/am...ms-report.html