How to interpret the parameters in a DIMM datasheet?

My current understanding:

• 8Gb(2Gx4)*36

  According to here:

The expression "8M x 8" describes one kind of 64Mbit chip in more detail. In the memory industry, DRAM chip densities are often described by their cell organi-zation. The first number in the expression indicates the depth of the chip (in locations) and the second number indicates the width of the chip (in bits). If you multiply the depth by the width, you get the density of the chip.

So the whole expression means 36 DRAM device/chips make up a DIMM (32 for storage and 4 for ECC). Each DRAM device/chip's density is 2Gx4 = 8Gb. 2G means the total locations. x4 means each bank in the device/chip has 4 arrays, which contributes 4bits for a location. The geometry details such as row, column and bank are not recoverable from this description.

• 1G x 8

  This means the DRAM device 1G locations with each location contribute 8 bits.

• 4G x 72

  This describes the DRAM module instead of single DRAM device/chip. But in a similar way. The 4G is the module depth in location count. And each location contributes 72 bits (I think 8bits are for ECC). So the module capacity is 4Gx64 bits = 32GB.

So the take away is: location count * location size = total size. This formula is used for both device density and module capacity notation.