Memory Flashcards
What is RAM?
RAM is high speed, volatile memory which is used as the main memory. IT CAN BE READ OR WRITTEN
What can be described as Volatile and Non-Volatile memory?
Volatile memory is temporary memory what requires power to retain its data
Non-Volatile memory is permanent memory which keeps its contents even when it has no power.
What does the main memory do?
The main memory is where all the data, files and programs are stored while being used
What happens when the computer is booted up?
The Operating System is copied from the secondary storage to the RAM.
What happens when Applications, documents and files are opened?
They are copied from the secondary storage to the RAM. They stay in RAM until the files or applications are closed. Applications, documents and files take up space in the RAM.
How fast is RAM?
RAM is slower than CPU cache but faster than secondary storage.
What is Virtual Memory?
Virtual Memory is Secondary Storage used as extra RAM.
As Computers have limited space in the RAM, what do they do when the RAM is full?
It moves the data that hasn’t been used recently to a location on secondary storage known as the virtual memory.
When is virtual memory needed?
Virtual memory is needed when to many applications are open at once or if a particular memory intensive application is being used or both.
What happens if the CPU needs to read data stored in virtual memory?
It must move the data back to the RAM. This is slow as data transfer rates are much slower on secondary storage than RAM.
What are the Cons of using Virtual memory?
Using virtual memory can make the computer slow to respond when switching applications (when data in virtual memory is swapped with each other) or when using memory intensive applications ( due to constantly moving between virtual memory and RAM just to keep program running
What is ROM and what does it do?
ROM is ‘read only memory’ and it contains all the instructions called BIOCS (Basic Input Output system) the computer needs to boot up. It is non-volatile and can only be read
.
Where is ROM located?
ROM comes on small, factory made chips built into the motherboard.
How is the ROM used?
As soon as the computer is powered on, the CPU reads instructions from ROM. It tells the CPU to perform self checks and set up the computer. e.g test the memory is working OK, see what hardware is present and copy the operating system to RAM.
Although the CPU can only read ROM it is possible to update (‘flash’) the BIOS on a ROM chip
