DRAM packaging

For economical reasons, the large (main) memories found in personal computers, workstations, and non-handheld game-consoles (such as playstation and xbox) normally consists of dynamic RAM (DRAM). Other parts of the computer, such as cache memories and data buffers in hard disks, normally use static RAM (SRAM).

General DRAM packaging formats

Dynamic random access memory (DRAM) is produced as integrated circuits (ICs) bonded and mounted into plastic packages with metal pins for connection to control signals and buses. Today, these DRAM packages are in turn often assembled into plug-in modules for easier handling. Some standard module types are:

* DRAM chip (Integrated Circuit or IC)
o Dual in-line Package (DIP)
* DRAM (memory) modules
o Single In-line Pin Package (SIPP)
o Single in-line memory module (SIMM)
o Dual in-line memory module (DIMM)
o Rambus modules are technically DIMMs, but are usually referred
to as RIMMs due to their proprietary slot.
o Small outline DIMM (SO-DIMM). Smaller version of the DIMM, used in laptops. Comes in versions with:
+ 72 pins (32-bit)
+ 144 pins (64-bit)
+ 200 pins (72-bit)
o Small outline RIMM (SO-RIMM). Smaller version of the RIMM, used in laptops.
* Stacked v. non-stacked RAM modules
o Stacked RAM chips use two RAM wafers that are stacked on top of each other. This allows large module (like a 512mb or 1Gig SO-DIMM) to be manufactured using cheaper low density wafers. Stacked chip modules draw more power.