Glossary

Capacity

Total number of available data memory cells on a module expressed in Gigabytes (GB). For kits, listed capacity is the combined capacity of all modules in the kit.

CAS Latency

A standard, predetermined number of clock cycles for data reads/writes to or from the memory modules and the memory controller. Once the data read/write command and the row/column addresses are loaded, CAS Latency represents the wait time until the data is ready.

DDR4

DDR (Double Data Rate) Synchronous Dynamic Random Access Memory (SDRAM) fourth-generation memory technology, more commonly referred to as “DDR4.” DDR4 memory modules are not backward compatible with any previous generations of DDR SDRAM due to lower voltage (1.2V), different pin configurations and incompatible memory chip technology.

DIMM Type

UDIMM (non-ECC Unbuffered Dual In-Line Memory Module) is a long form-factor memory module with a data width of x64, most commonly used in desktop systems where error correction is not required and DIMM capacity is restricted.

SODIMM (Small Outline Dual In-Line Memory Module) is a reduced form-factor memory module intended for smaller compute systems, such as laptops, micro servers, printers or routers.

Kit

A part number that includes multiple memory modules, typically in support of dual, triple, or quad channel memory architecture. For example, K2 = 2 DIMMs in the package to equal the total capacity.

Speed (a.k.a. Frequency)

The data rate or effective clock speed that a memory module supports, measured in MHz (MegaHertz) or MT/s (Megatransfers per second). The higher the speed, the more data can be transferred per second.