DDR4 memory organization and how it affects memory bandwidth
Apr 19, 2023Xiaomin Shen

Summary
This post details the impact of DDR4 memory organization, specifically rank and organization (e.g., 1Rx8, 2Rx4), on memory bandwidth performance. It explains memory rank as sets of DRAM chips on a module, dual-rank and quad-rank modules doubling or quadrupling capacity and using rank interleaving for reduced response time. It also covers memory depth and width, how memory device width (x4, x8, x16) affects the number of chips per rank and module capacity, and the relationship between page sizes and timing parameters like tFAW, which is influenced by memory device width and DDR4 speed.
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