SystemRAM

SystemRAM, or system random-access memory, refers to the primary volatile memory used by a computer's central processing unit to store data and instructions that are actively in use. It sits on modules (often DIMMs or SO-DIMMs) on the motherboard and provides much faster access than storage devices, though it is volatile and loses its contents when power is removed.

System RAM is typically implemented as dynamic RAM (DRAM), with performance influenced by capacity, speed, and timing. Modern consumer systems use DDR (double data rate) SDRAM, with generations such as DDR4 and DDR5. Performance is described by capacity (how much data can be held) and bandwidth/speed (how quickly data can be read or written), often indicated by metrics like MT/s and CAS latency. Memory can be configured in single, dual, or quad channel modes, which affect throughput. In professional or server environments, error-correcting code (ECC) RAM may be used to detect and correct certain memory errors.

Capacity and speed have a direct impact on system responsiveness. Sufficient RAM allows more applications to run concurrently and reduces reliance on slower storage-based paging. When RAM is insufficient, the operating system uses swap or paging space on a storage device, leading to slower performance. RAM compatibility depends on factors such as motherboard support, CPU memory controller, module type, voltage, and timing specifications. Common desktop configurations range from several gigabytes to multiple tens of gigabytes, while servers and workstations may require much larger amounts.

RAM is distinct from cache memory and non-volatile storage, serving as the fast, temporary workspace that underpins active computing tasks.