Memory and Storage Flashcards
What is the purpose of memory?
Memory is where data and programs are stored either permanently or temporarily.
Why is RAM used to store running programs rather than the hard disk?
The hard disk is slower to access than the RAM. If programs that were running had to be fetched from the hard drive all the time the computer performance would be a lot slower.
What is meant by volatile memory?
Volatile memory loses its data once power to the memory chip is interrupted or lost.
RAM is a read/write type of memory. What does this mean?
Read/write memory is when the CPU can read data from the memory and also write data into it.
What does the random part of RAM refer to?
The CPU can access any memory location, at any time, in any order. Also any location can be used to store data. Because of this, programs held in RAM can run very quickly.
Describe how DRAM temporarily retains data.
DRAM requires a constant refresh signal to keep its capacitors charged, otherwise data is lost.
Where are you most likely to find DRAM being used in a computer system?
In RAM.
Where is SRAM most likely to be used for in a computer system?
In cache.
What are the differences between SRAM and DRAM?
SRAM is faster to access than DRAM.
SRAM is more expensive than DRAM.
DRAM requires a refresh signal to keep data intact, where as SRAM doesn’t.
Define ROM.
ROM is read only memory. It cannot be changed, overwritten or removed, only read. It stores the computers boot up instructions. It’s non-volatile.
What are the differences between RAM and ROM?
RAM is volatile, where as ROM is non-volatile.
RAM holds data and instructions, where as ROM is used to hold computer hardware settings.
You can read and overwrite RAM, whereas you can only read ROM.
What is the purpose of flash memory?
Flash memory is a non-volatile memory chip used for storage and for transferring data between a PC and digital devices. It has the ability to be electronically reprogrammed and erased. It is often found in USB flash drives, MP3 players and digital cameras.
What are three differences between flash memory and a hard disk?
Flash memory is faster and more reliable.
Flash memory has no moving parts, unlike a hard disk.
Flash memory degrades a little every time data is written or erased so eventually is will wear out.
What is the purpose of virtual memory?
As RAM fills up to capacity, the OS can temporarily mark sections of the hard disk to use as virtual memory to stop the computer crashing.
What are three tasks that the BIOS does during the boot up phase?
It carries out a number of basic checks (self-diagnostic tests) on the system, such as is the memory ok, does the hard disk work.
It loads the OS.
It provides a basic user interface.
