Last updated: August 11, 2021

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Welcome to our big processor test 2021. Here we present all the processors we have tested in detail. We have compiled detailed background information and added a summary of customer reviews on the internet.

We want to make your purchase decision easier and help you find the best processor for you.

You will also find answers to frequently asked questions in our guide. If available, we also offer interesting test videos. Furthermore, you will also find some important information on this page that you should definitely pay attention to if you want to buy a processor.


  • The processor is the heart of personal computers and notebooks, it is responsible for the execution of (computing) tasks.
  • Its performance depends, among other things, on the number of cores, the clock speed (in GHz) and the cache.
  • A distinction can be made between processors for office PCs, mid-range processors and high-end and gaming processors.

The best Processor: Our Picks

Guide: Questions you should ask yourself before buying a processor

What is the purpose of a processor and how is it constructed?

The processor or CPU (Central Processing Unit) is often called the heart of the computer because it works in a regular rhythm (clock frequency). It is a component measuring a few square centimetres that contains highly integrated circuits for controlling the computer and calculating data.


To prevent CPUs from getting too hot, cooling solutions such as fans are very important. (Photo: tookapic /

A processor drives algorithms by receiving, decoding and executing instructions. Since it is responsible for the calculations in the computer, it is often compared to the brain. The faster the clock, the faster it can process commands.

The classic structure of a CPU is:

  • Arithmetic Logic Unit (ALU),
  • Control or management unit
  • Memory controller or memory management unit
  • Cache (memory) and
  • Data lines (buses) for communication

Where is the processor located?

The CPU sits on a socket, i.e. a rectangular slot device attached to the motherboard. Above the socket and processor, there is usually a fan.

What is the difference between a processor for notebooks and for desktop PCs?

The necessarily compact design in laptops and the requirement for mobility mean problems with cooling and energy consumption for hardware manufacturers.

Desktop processors have the advantage that more space is available for coolers.

In addition, desktop computers are constantly connected to the power grid. High energy consumption is not as dramatic as with laptops, which should run for as long as possible without a mains connection, but only on battery power.

In the meantime, however, at least the processors of gaming laptops are often almost on a par with their desktop counterparts. In ultra-slim notebooks and cheap office laptops, however, weaker processors are usually installed because they are more energy-efficient and get less hot.

Did you know that a processor reaches a temperature of 30 to 50°C in normal operation?

Under full load, temperatures can even reach 95°C and more.

What does processor clock frequency mean?

The clock frequency is the rate at which the processor can process a simple instruction such as an addition.

It is given in hertz, where one hertz means 1 clock per second. The higher the clock frequency of the processor, the faster the computer is in principle, because the calculator can process more instructions in a given time.

Basically, the higher the clock frequency (in GHz), the faster the CPU. In practice, however, the performance depends on numerous other elements, such as the number of cores or the cache.

Keep in mind, however, that clock speed is far from the only factor that determines speed and performance. Current CPUs have a clock frequency of several gigahertz (GHz = billion hertz).

Did you know that the processor used in the moon landing had a clock frequency of only 1.024 Mhz?

Today's processors often have a clock frequency of 3 Ghz and more, which is almost 3,000 times higher than back then!

What is the processor cache?

The processor cache is a buffer memory that is now usually attached directly to the processor. It is a fast buffer memory that ensures that the processor does not have to constantly access the slow main memory.

It only does this when it cannot find what it is looking for in the cache. The size and speed of the cache are therefore also important for CPU power.

In fact, processors usually have two or three cache levels. The closer a memory level is to the computer core or register, the faster it can be accessed.

The fast cache of level 1, for example, has stored the most frequently used instructions and data. The lower and faster a cache level is, the less memory it provides.

Cache coherence protocols ensure that data uniformity exists in systems with more cores and several CPU caches and that no permanent inconsistencies occur.

The Memory Management Unit (MMU) Unit translates the virtual addresses into real ones and manages access to the main memory.

What are threads on the processor?

In terms of the processor, threads are virtual cores. A four-core processor that supports so-called hyperthreading can offer eight virtual cores to the system. Hyperthreading can therefore virtually double the number of cores and thus increase performance.

However, eight physical cores are still more powerful than eight virtual ones. Threads share some of the execution units of the physical cores. Thus it happens that one has to wait until the other has finished using it.

What are the benefits of more processor cores?

Nowadays, manufacturers usually combine several CPU cores. The individual cores work independently of each other and have their own computing units and registers; only buses and parts of the cache are shared.


CPUs are fixed to the socket with a lever. (Photo: alyssonrock /

Since the cores share the work among themselves and work in parallel, the performance can often be multiplied. However, the extent to which this is possible in practice depends on how well the software parallelises and how many cores it can support.

Games currently support mainly computers with four cores, although those with eight cores can be considered investments for the future.

Whether more cores bring an increase in performance depends on the task and how far it can be parallelised.

Computers with several cores also pay off with a lot of multitasking, for example when you run a game on one monitor and use internet pages and applications on a second monitor at the same time.

Multi-cores also give you an advantage if you are doing 3D rendering or video editing, or if you are dealing with high-resolution audio data.

For other applications, however, the performance of the processor can be much better increased by increasing the clock speed. The actual increase in performance brought about by multiple cores must therefore always be considered on a case-by-case basis.

What should I look for in a processor?

At present, almost only processors from Intel and AMD are used. The product names already tell you a lot about the features of the processors. This will be demonstrated below using the very prominent Intel Core i processor family. If the CPU is called i7-7700K, for example, this means the following:

characters Meaning

The first two characters ("i" + number) indicate the performance class at the beginning. This is determined by several characteristics such as the number of cores, support for hyperthreading or support for turbo boost.

For gaming notebooks, at least i5 (=upper mid-range) or better still i7 (high-end) processors are usually suggested, for mid-range PCs i3. Higher is generally better here, but the performance class is not yet sufficient for absolutely reliable performance determination.


The performance class is followed by four digits, the first of which stands for the processor generation. Higher numbers here mean a later generation and are again basically better.

The latest processor generation is the eighth with the performance classes i3, 5, i7 and i9.

700 The next three digits of the model number indicate the item number, which is determined by other features and the release date.

You should, however, pay attention to the letter appendages after the model number.

For desktop CPUs, no suffix means a standard model. "T" models have a lower clock speed and are suitable for office PCs. The letter suffix "K" stands for Unlocked, which means an open clock multiplier (only for i3, i5, i7 and certain Pentiums). This enables an increase in performance and is mainly used for gaming.

For notebook processors, "U" stands for a special economy, the clock rate is lower. The abbreviations "HK" and "HQ", on the other hand, stand for High Performance Graphics Unlocked and High Performance Graphics Quad, respectively, and indicate particularly high performance for gaming notebooks.

For office PCs, Intel often offers processors from the Celeron or Pentium family.

With AMD, too, the basic performance can often be recognised by the name. For example, there is the Threadripper for the absolute high-end range and below that the AMD Ryzen 7, AMD Ryzen 5 (mid-range) and AMD Ryzen 3 (office PC).

This designation is followed by a four-digit model number. The higher this number, the more powerful the individual model. The suffix "X" means a slightly higher base clock and better support for the boost system XFR.

Image source: Alexandru-Bogdan Ghita /