It depends on the module, but for example a 1 gigabyte DRAM module can be built from sixteen 64 meg x 8 chips. Each chip is 8 bits wide, so 8 chips give you 64

It depends on the module, but for example a 1 gigabyte DRAM module can be built from sixteen 64 meg x 8 chips. Each chip is 8 bits wide, so 8 chips give you 64 bits. This is duplicated for two banks. The row and column addressing is repeated in each chip, while the circuitry to select the right module and bank is external. I'm sure someone else can provide more details on modern modules. One reference is http://www.softnology.biz/pdf/lecture05-dram.pdf http://www.softnology.biz/pdf/lecture05-dram.pdf