1.3 Memory

1.3 Memory

1. RAM

   • RAM - Random Access Memory
     • Read-Write access
     • Types of RAM
       • DRAM - Dynamic Random Access Memory
         • Uses transistor ans capacitor to represent and store a bit of data - charge needs to be refreshed every few seconds
           • Main RAM
       • SRAM - Static Random Access Memory
         • Uses a group of transistors combined for each bit of data - do not lose charch so it is faster than DRAM - can be non volatile when used in flash memory in dtorage and ROM
           • Cache - more expensive to make and build than DRAM

2. ROM

   • Read Only Memory
   • Non-Volatile
   • Contains BIOS (Basic Input Output System) -firmware for the motherboard
     • Contains BOOTSTRAP - the program that instruct the computer on how to boot and load the operating system
       • Process happens between powering on and beeping to say the OS is loading - this is known as POST (Power On Self Test)
   • Types
     • PROM (Programmable Read-Only Memory)

3. A Type of Volatile: RAM

4. 6 Mark Question

   • Q: A gamer has bought a new computer and it is running slow. It has a 1TB hard disk, a quad-core CPU and 8MB of memory - Why is the computer slow?
     • A:

5. Volatility

   • Volatile - Contents is wiped when power is removed
   • Non-Volatile - contents is saved even when there is no power

6. Storage

   • 2 Types of Non-Volatile: ROM, Hard drive
   • 3 Types: ROM, RAM, Backing Stores (hard drives)