Everything You Need to Know to Choose a CPU

A CPU

Whether you are building a new PC, upgrading your existing system or deciding the specifications for a new laptop, choosing the right CPU is one of the most important steps in that process.

First of all, I want you to know why are you buying the CPU and how will you use it? Keep the answer in mind we will need it later. Also, it’s worth knowing that a good CPU isn’t enough for a fast PC, you should pair it with a good RAM and one of the best SSDs. Gamers, graphics designers and video editors should get one of the best graphics cards (GPUs) too.

What Is a CPU?

The CPU is short for Central Processing Unit. It is the portion of a computer that retrieves and executes instructions. In short, the CPU is the brain of the computer. It is often simply referred to as the processor.

What Could Go Wrong If You Don’t Choose Your CPU Wisely?

  • Slow performance, fewer cores than needed and lower clock speed will cause slow performance.
  • Non effective multi tasking, having less cores than what you need will effect multi tasking negatively.
  • Problems like the blue screen, using a low end CPU for heavy tasks is one of the things that result in blue screens.
  • Not being able to use your CPU, if you are building a PC, choosing a CPU that doesn’t support your CPU socket and chipsets won’t make you able to use your CPU.
  • Losing money, yes, if you buy a CPU with more features than you actually need you will end up losing money.

Factors To Consider When Choosing a CPU

Important information about some AMD CPUs
Specifications and important info for some AMD CPUs

There are lots of factors when it comes to choosing a CPU, we have most of them here, from the most important things to things you shouldn’t worry yourself about. Before we start, you should know that when comparing CPUs, most of these factors are only relevant if you are comparing two CPUs from the same generation and the same company. If you want to know how a particular CPU performs then you should search for reviews and benchmarks.

Cores And Clock Speeds

  • Cores: they are a CPU’s processor and they can only work on one task at a time. Think of it as offices in the CPU, each office can’t work on more than one thing at the same time. The more offices you have, the faster the job gets done. Most CPU’s today have betweeen 2 and 18 cores, don’t aim for less than 4 cores if you can afford it.

    Lightly threaded apps like games don’t need a lot of cores, but video editing and animation programs will run much faster, much effectively with more cores.
    Side note: Intel has a brand named “Core” (ex: intel core i9-12900k). That doesn’t mean that other CPU’s don’t use cores, it’s just a brand name.
  • P-Cores vs E-Cores: Performance cores and efficiency cores are new types of cores that Intel started using in its 12th gen CPUs. To keep it short and simple, by using this architecture Intel wants to improve multitasking and improve the performance of P-Cores (the main cores) by giving smaller tasks to efficiency cores.
  • Clock Speed: (“clock rate” “frequency”) indicates how fast your processor deals with instructions and calculations, it measures the number of cycles your processor excutes per second in GHz (billion cycles per second). The higher your clock speed, the faster the cores within the CPU will perform.
    When you see the clock speed of a procesor, please note that this is actually the speed of the cores not the CPU itself.  A four-core 3.0GHz processor has four processing units each with a clock speed of 3.0GHz. The four core processor we just described has a total clock speed of 12.0GHz.

Compatibility

A CPU getting installed in its socket
A CPU getting installed in its socket
  • CPU Socket: There are two types of CPUs, soldered and socketed. Soldered CPUs, can’t be removed, replaced or upgraded. Socketed CPUs are placed on the motherboard through sockets, that means they are replacable and they can be upgraded. If you already have a motherboard you have to pay attention to whether your CPU supports its socket or not. If not, you might consider having enough budget for a new CPU and a motherboard.
  • Chipsets: A chipset controls and manages the data flow between components on a motherboard, including the CPU.

    Knowing the chipset you are getting will not only tell you whether it’s compaitable with your CPU or not, but it will also give you an idea about the features you are getting.

Useful to Knows

  • Bottlenecks: A bottleneck happens when some components in the PC limit the performance of other components. For example, you expect your PC to give you high performance because you have a strong CPU, but instead it’s giving you less than you expected, mainly because another component (RAM, GPU, etc.) is limiting the performance.

    This isn’t something the average user who only uses their PC for daily tasks might experience. However, people who use their PCs for more advanced tasks like gaming or video editing might experience this.
    To prevent a bottleneck make sure that all of your components are powerful enough to give you the performance you want.
  • TDP: It stands for Thermal Design Power, measured in watts, it refers to the maximum amount of power your CPU can consume. There is no such thing as a “perfect TDP value” but knowing the TDP value is very important. For example higher TDP means that your processor is using more electricity and genrating more heat. You will need a strong cooler for a processor with high TDP. Your maximum power cosumption can’t exceed your TDP value. However, during turbo or certain workload types it can exceed the maximum TDP but only for a limited time, or:
    • Until the processor hits a thermal throttle temperature, or
    • Until the processor hits a power delivery limit.  

Very Technical

We are officially at the very technical zone. Knowing most of that stuff doesn’t really matter for most people, unless you are already knowledgeable in PC hardware.

  • PCIe: It stands for Peripheral Component Interconnect express. If your CPU supports a newer PCIe generation this means that you will have better connection between high speed components, (CPU, GPU, SSD, etc).
  • Overclocking support: Overclocking is important for a lot of people since it enables them to get better a performance with their processor. Basically overclocking is pushing your CPU past its official limits and forcing it to run faster than it’s intended to go. Not all CPUs support overclocking. So, if you want to overclock check if the CPU supports that first. Be careful though, overclocking can damage your CPU if you don’t use it wisely and with caution. So, please when you overclock your CPU do it with caution to avoid fixing your CPU or buying a new one.
  • IPC: It stands for Instructions Per Clock/Cycle. It tells you how many instructions/things a CPU can do in a cycle. We mentioned clock speed in must-knows and we explained that it refers to the number of cycles a CPU can do in a second. IPC refers to the number of things a CPU can do in each of these cycles. You aren’t likely to see a number in the offocial AMD or Intel website telling you how many Instructions a cycle can do, but you might see them telling you that there is an increase in IPC by % compared to the last generation for example.

CPU Cores Number vs Clock Speed

It is so important to know where to spend your money. Should I buy an eight-core 2.40 GHz processor? Would it be better if I bought a four-core 4.0 GHz processor. Is it worth buying an eight-core 4.0 GHz processor? All of these are thoughts that you might have, we will answer them one by one.
Do you remember the question in the beginning? “Why are you buying the CPU and how will you use it?” depending on the answer you will be able to choose the right cores number and clock Speed for you.

More cores and lower clock speed, this option is perfect for people who usually run multiple non-heavy applications at the same time, or use applications that benefit from having more cores. Video editors, engineers, data analysts are people who should prioritise cores number over clock speed.

Less cores and higher clock speed, programs that can’t split tasks between multiple cores and they benefit from two or less cores need more clock speed. Higher clocks translate to quicker responsiveness and program load times. Audio editing, some popular games and certain older applications are examples of applications that need more clock speed. It’s worth noting that programs/applications these days tend to benefit from more cores, even new games are being designed to benefit from multiple cores instead of focusing on one or two cores.

Types Of Uses For CPUs

Light Workloads And Budget

If you want a processor that is suitable for web surfing, watching youtube and light tasks like using excel, spreadsheets and word then you might want to buy an Intel Celeron. Or, if you are looking for better performance then you should consider investing in an Intel Pentium, or in an AMD Athlon which is considered to be one of the best CPUs in this category. Don’t expect these processors to do more than light workloads.

Right now the i3 Ryzen 3 are the kings when it comes to budget CPU. Yes, you will pay more but you will be able to complete more performance demanding tasks and you will be able to do some casual gaming too which isn’t possible with other budget CPUs.

Personal Use/Gaming

These type of chips are the sweet spot for almost everyone because they have an affordable price, yet they provide really good performance. You can use them for everyday use and for gaming. You can opt for a good i5 model or a good Ryzen 5. These types of CPUs are just perfect, high-end i5 and Ryzen 5 processors have high clock speeds and a reasonable amount of cores which is great for gaming.
As for gaming performance, the GPU is usually more important than the CPU, throwing all of your budget on a CPU and ignoring your GPU is a bad idea. Also, as I mentioned earlier games tend to benefit from single-core performance more than the number of cores so keep that in mind. And while there are games that use more than 6 cores, currently they are just exceptions for the general rule, at least for now.

Creative Media Work

Content creators and streamers who play heavy games while streaming and people who use power-intensive software like VR or autoCAD should opt for these type of CPUs. Also, this is an ideal option for 4k video editors architects and graphic designers, if you want to save some money and get a powerful CPU at the same time, without buying an Intel Xeon or a Core X chip. An i7 if or a Ryzen 7 CPU will do just fine, however if you have the money and you need more performance consider going for an i9 or a Ryzen 9.

Workstation

When you think about something that can handle massive databases, complex math, 8k video editing and scientific tasks what comes to your mind? Intel Xeon, AMD Ryzen Threadripper and AMD EPYC. These monsters are designed to manage data-heavy workflows and their only goal is to get tasks done. Now, speaking from a practical point of view these processor aren’t for everyone, and most of them are expensive for the average user, why? Because they are designed for special applications and uses that require a lot of processing power.

Steps Of Buying a CPU

If it’s your first time searching this topic you are probably overwhelmed at this point so we are going to tell you what to do.

  • Know your needs and your budget
  • Get a general idea about the terms explained above like core count, clock speed, etc.
  • After knowing what these terms stand for, watch some reviews. They will give you an idea about the performance that you should expect and might even recommend different CPUs for different needs.
  • When you decide what CPU you are going to buy check if it’s compatible with the rest of your build, like your motherboard and CPU cooler. If not, you will either need to choose a different CPU or change some components in your build.