What is a CPU and How Do I Monitor its Usage?
All kinds of computing devices such as tablets, PCs, or laptops feature a brain-like unit called the central processing unit or CPU. Your computer's CPU calculates and interprets instructions while you’re surfing the web, creating documents, playing games, or running software programs. It’s a critical component that your PC can’t function without.
Below, we’ll dive into why a CPU is so important and how to monitor your CPU usage to ensure optimal system performance.
What is a CPU?
A CPU is a small but mighty computer chip found on top of the motherboard in your PC. It’s placed into the CPU socket with its pins facing down. A small lever keeps it secure.
CPUs generate a lot of heat, even when running for a short amount of time. Due to this thermal activity, the CPU is usually attached to a heat sink with a fan located right on top of it. In most cases, these two components will arrive bundled if you buy a CPU.
Your CPU is different from the GPU (graphics processing unit) which renders images and video on your display. With that said, there are integrated GPUs that exist on - and share memory with - the CPU. There are also standalone GPUs (called dedicated GPUs) that have their own card and memory.
CPUs are also sometimes confused with a PC’s memory, but that is a whole separate component where information is stored on your computer.
CPU construction and history
The world’s first commercial CPU was introduced in 1971. It was the Intel® 4004, which was a 4-bit CPU. It clocked at 740 KHz and could execute up to 92,600 instructions per second. Five months later, the first 8-bit CPU was introduced, the Intel 8008. To put this in perspective, the latest Intel chip, the i9 clocks at 5.0 GHz and can handle over a million instructions per second.
CPUs are constructed by placing billions of tiny transistors onto a computer chip. These transistors are what allow the CPU to perform calculations and run programs from your PC.
As CPU technology has advanced over the years, transistors have gotten smaller and smaller in size. This means that chips can have many more transistors with each generation, thus improving the overall speed of a CPU.
The co-founder of Intel, Gordon E. Moore predicted this trend in 1964 which became known as Moore’s Law in the tech industry. Moore’s Law suggests that the number of transistors on a chip doubles every two years while the cost of general computing devices falls.
Although it’s more of an observation than a “law,” it’s remained true that transistors have steadily increased in number and decreased in size. The doubling of transistors installed on computer chips now occurs about every 18 months instead of every two years, however.
As CPU technology has progressed, the clock speed and functions of CPUs have made monumental improvements.
CPU components
There are two primary parts of a CPU:
Arithmetic Logic Unit (ALU)
The ALU of a CPU executes mathematical, logical, and decision-making operations in your PC. It can execute four kinds of mathematical operations including addition, subtraction, multiplication, and division.
The logical operations it performs are usually in the form of comparisons that involve numbers, letters, or special characters. This comparison operation is what allows your computer to discern whether or not your credit card has reached its credit limit or whether there are empty seats on an airplane, for instance.
Control Unit (CU)
The control unit of your CPU directs all the processor’s operations and fetches instructions from memory.
How a CPU processes data
If you’re curious about how all of these different components work together to perform an action on your computer, let’s run through the steps involved.
Before your CPU can do anything, program instructions and data need to go into memory via an input or storage device. Once the data and instructions are available, the CPU goes through the following steps for each instruction it retrieves.
I-time, E-time, and machine cycle
- The CU fetches the instruction from the memory.
- The CU decides what the instruction means and directs the relevant data to be moved from memory to the ALU. These first two steps combined are called instruction time or I-time.
- The ALU executes the arithmetic or logical instruction.
- The ALU stores the result of this operation in the memory. Steps 3 and 4 together are referred to as execution time or E-time.
- The control unit directs memory to release the result to an output device or storage. I-time and E-time together are called the machine cycle.
CPU cores
Some PCs or devices use a single-core processor while others might have a dual-core or even a quad-core processor. Running two processor units simultaneously enables the CPU to retrieve twice the number of instructions every second which enhances performance.
Some CPUs can virtualize two cores for every actual core in your processor which is called hyper-threading. Hyper-threading is when a processor with two cores functions like it has four, and so on. With that said, physical cores are still more effective than their virtual cousins.
How to check CPU usage
1. On the Windows 10 operating system, you’ll need to enter the Task Manager to view real-time CPU information. Here are a couple of ways to get there:
- Right-click the Taskbar and click on Task Manager
- Open Start, do a search for Task Manager and click the result
- Use the Ctrl + Shift + Esc keyboard shortcut
- Use the Ctrl + Alt + Del keyboard shortcut and click on Task Manager
- Use the Windows key + X keyboard shortcut to open the power-user menu and click on Task Manager
2. After you’ve gotten to the Task Manager window, you’ll need to get to the Performance tab. To do this, you may need to click on the More details button, then choose the Performance tab.
3. When you’ve entered the Performance tab, you’ll be able to view four parts of your computer: your processor, memory, hard drive, and Bluetooth.
4. In the left section of the window, you’ll see these computer components with a graph showing their activity levels in percentage for CPU, Memory, Disk, and Kilobits per second for network adapters.
5. To view just a summary of these CPU usage stats, you can right-click below the components and choose Summary view.
How do I improve my CPU’s performance?
To improve your CPU’s performance, there a few steps you can take. In most cases, computers use only a tiny portion of their total CPU power.
To see what applications are taking up the most CPU, open up your Task Manager window to see the currently running processes. You can then click the CPU header to organize and sequence the processes based on CPU usage.
You may find an unnecessary background application running or an errant process running that’s eating into your CPU. If this is the case, simply click End Process which will quit the application.
Note: If you find that your CPU is being maxed out by regular applications, it’s likely that you either need a faster computer or you may be able to add more RAM.
With these tips, you’ll be on your way to becoming a knowledgeable computer user who can monitor and manage CPU usage with total mastery.
