RAM

Random Access Memory (RAM)

• RAM is a temporary storage for data and programs that are being accessed by the CPU

• RAM = volatile memory, meaning the contents are erased when the computer is turned off

• More RAM means more capacity to hold and process large programs and files, as well as enhance system performance

• If your computer is low on RAM, it will use virtual memory

Types of RAM

• For purposes of test, the Double Data Rate (DDR) series is the most important to know because acts as the standard for computers

  • Oldest versions consume more power

  • Oldest version are the slowest

  • Oldest versions are the cheapest

    • DDR SDRAM

    • DDR 2 SDRAM

    • DDR 3 SDRAM

    • DDR 4 SDRAM

  • Other types of RAM…

    • Dynamic Ram (DRAM) - cheap and slow

    • Static Ram (SRAM) - extremely fast and expensive to implement

      • Typically used for CPU Cache- small piece of personal memory for CPU for important file locations and data

    • Synchronous DRAM (SDRAM): data provided to CPU at a rate matching the CPU’s clock cycle

RAM Form Factors

• DIMMs: used for desktops and servers - physically thicker

  • DDR 4

  • DDR 3

  • DDR 2

• SODIMMS: used exclusively for laptops - physically smaller

  • DDR 4

  • DDR 3

  • DDR 2