OCR_Computing_GCSE_Hardware Flashcards
What is cache memory?
The fastest type of memory, attached to the CPU it is small and used for current instructions and data storage.
What is clock speed?
Clock speed describes how quickly the computer can fetch and execute instructions. It is measured in Hz.
Why do most modern CPU’s have multiple cores?
Because each individual core can only do one function at a time so it increases overall performance
From lowest to highest what are the measurements of data size? bits…..
bits, nibble, bytes, kilobytes, megabytes, gigabytes, terabytes
Define the purpose of the CPU
The purpose of the central processing unit (CPU) of a computer is to:- fetch instructions from main memory- fetch data from main memory- decode the instructions- execute the instructions- performs calculations- manages the movement of instructions and data to and from peripheral devices
What does quad-core mean in terms of the CPU?
This means the processor actually has 4 processors on the chip. It means it can fetch and execute up to 4 instructions simultaneously. (Operating systems and software have to be written so that they take advantage of multiple cores, or they will only use one at a time.)
What does 3GHz mean in terms of the CPU?
This is the speed at which it operates. The higher the number the quicker it can fetch and execute instructions.
What is a system bus?
The circuits/internal wiring that connect the processor and main memory together.
Explain how the clock speed affects the performance of the CPU.
The faster the clock speed (measured in Hz), this is the number of electrical cycles per second. The fast it is the quicker it can fetch and execute instructions.
Explain how the number of cores affects the performance of a CPU.
The more cores a CPU has the more instructions it can fetch and execute at the same time. Multiple cores are only useful if the operating system and program are written to take advantage of them, if they are not optimised for multiple cores then only one core will be used.
Explain how the cache memory affects the performance of a CPU.
The cache is attached to the CPU, it is the fastest memory available in the computer. More cache memory means that more of the frequently used instructions and data can be accessed quickly, improving the performance of the computer.
What is ROM?
Read Only Memory: memory that is hard-coded at the time of manufacture. Stores the boot-strap loader, which loads the operating system. Non-volatile, the instructions remain after the computer is turned off.
What is RAM?
Random Access Memory: a type of memory that is read-write and volatile. Used as the main memory of the computer. It is used to store the programs and data that are currently loaded on the computer. Traditionally it comes as ‘sticks’ made up of chips that plug into the motherboard.
Which is non-volatile, RAM or ROM?
ROM.
What is the difference between ROM and RAM?
RAM is computer memory which loses its data when the computer is switched off.ROM is computer memory which retains its data, even when the computer is switched off.
What is flash memory?
Secondary storage that has no moving parts. Used in memory sticks, cameras and phones. Made of silicon chips.
