Where does the CPU store Its computations? – A quick answer
So, the answer is straight- The CPU stores its computations in registers. Resisters are a sort of temporary memory for the CPU, a super-fast but little memory.
Quick view
What is CPU?
The primary function of the CPU is to take input in the form of instructions and interprets what is the requirement to give the result. The CPU is a complex piece of hardware that processes all data that enters and leaves your computer. But do you know where does the CPU store its computations? The answer is simple.
Where does the CPU store Its computations?
But are you curious to know where the CPU stores its computations after holding them in the registers? The CPU stores its computations into cache and CPU RAM after it stores it to the registers. So, when you have an answer to where the CPU stores its computations, let us have a deep look at registers.
What are registers?
A register is a quickly accessible location for the CPU to store its computations. Registers can be differentiated based on the number of bits they can hold. For example- 8-bit registers, 32-bit registers, 64-bit registers, etc. A 32-bit register is faster than an 8-bit register, and a 64-bit register is faster than a 32-bit register.
Types of registers
We have discussed that they are registers where the CPU stores its computations. Let us have a quick look at the main types of registers.
1. User-accessible register
These registers can be read or written by machine instructions. User-accessible registers can be further divided into three main types based on the information that they hold.
- Data registers- These hold numeric values, characters, small bit arrays, and some other data.
- Address register- These hold addresses and are used by instructions that indirectly access primary memory.
- General-purpose registers- These can hold both addresses and data.
2. Internal registers
Instructions can not access these registers; they can only be used for processor operations internally. Some of the main types of internal registers are- instruction register, memory buffer register, memory address register.
3. Architectural registers
These registers generally do not correspond to the physical hardware as they are visible to the software-defined by architecture.
Where does the CPU store Its computations- A quick view to types of storage
The CPU stores are computations and calculations at two types of storage-
- Primary storage
- Secondary storage
So, let us see the two types of storage, one by one that the CPU uses to store its computations- Primary memory and secondary memory.
Primary Memory
Want to know where does the CPU store its computation? Let us begin with Primary memory. Primary memory is the memory directly assessed by the CPU. The Primary memory includes different types of memories such as cache, system ROM and Random-access memory (RAM).
RAM is a volatile memory, which means it is lost when there is a power cut. Random-access memory consists of memory modules that temporarily store data while a system is running. So, there is always a need to load secondary memory to the operating system into primary memory.
Also, when an application is launched in your system, it is loaded into RAM. It is because RAM, i.e., primary memory, is much faster than other storage devices. The data exchange between RAM and CPU is more than a hundred times faster than between CPU and storage devices.
When you load data into RAM, the programs are more responsive and run much quicker than when accessed from secondary memory. So, Primary memory is most often called Primary storage, where the CPU stores its computations.
Secondary Memory
The computer memory that is non-volatile and persistent is called secondary memory. Secondary memory can’t be accessed directly by the computer or central processing unit (CPU). You can also call secondary memory secondary storage for CPU computations.
Secondary memory consists of all permanent non-volatile devices like- ROM (Read-only memory), magnetic tapes, hard disk drives, flash drives, etc. But secondary memory can be accessed only by the primary memory and transferred to the processor after that. As you know already, secondary memory is slower than primary memory, but it can store data even after a power cut.
Conclusion
I hope now you know that where does the CPU store its computations? CPU keeps its calculations to the registers at first because registers are the fastest of all storage. Registers are tiny but spacious enough to fetch and hold small data quickly. After that, the data is transferred to cache and RAM.
