This series of articles has two purposes at the same time: educational and commercial. They will try to explain as clearly as they are what the various PC components are and at the same time they will guide you in choosing the best components for your purposes.
La CPU it is the central computing unit (Central Processing Unit) of an electronic computer, like a computer, but also a console. His job is to manage the machine globally. We can say that its fundamental purpose is to execute the instructions of the programs that require logical, arithmetic computational skills, the ability to move data between the memories and command any other peripheral instrument.
In video games they are responsible for executing the logic of the game, managing artificial intelligence, preparing the elements that are on the scene and communicating them to the graphics card and managing the audio.
core: for Core, we mean the unit that actually performs the calculation of the processor, plus the outline of the circuitry that helps it to function. Within the same structure, called package, there may be more than one Core present. Having a larger number of cores allows the computer to execute multiple things at the same time or to split a parallelizable workload on multiple computing units to run it faster.
TDP: this code indicates the Thermal Design Power, that is the heat that must be disposed of by the cooling system. It represents neither the true consumption of the processor nor the actual heat during peak work, which may be greater.
socket: this is the term used to indicate the processor socket. Each CPU must be inserted on a motherboard that has the same socket and is recognized as compatible. In the socket there are all the electrical connections necessary to let the processor communicate with the rest of the system and supply it with energy.
Architecture: the electronic layout of the CPU. More specifically, it indicates how the various sets of instructions to be performed are physically implemented. A single set of instructions can be physically implemented in many different ways. The architecture determines the overall performance of the processor.
Lithography: the lithograph indicates the production process of a CPU and indicates the average size of the gate of the single transistors. The smaller this value, the more it indicates the use of a recent production process able to obtain a high density of transistors and a better energy efficiency. Today we have arrived at quantities of the order of nanometers. The value in itself does not say everything though, because every semiconductor factory has a specific and different process, so it is useful to indicate in addition to the size, also the producer.
At every change in the production process, there is usually a change in the nomenclature of the processors and a different name for the architecture.
Simultaneous Multithreading: the architectures of modern processors are very complex and are not always exploited at 100%. Therefore a hardware method has been studied to improve its efficiency. Intel calls it HT, AMD uses the generic term abbreviated with SMT. This allows multiple threads (sequences of sequential program instructions) to be run simultaneously on one core. In the operating system this is seen as an extra core to which to assign work. For this a CPU with 2 physical cores with HT technology, is seen by Windows as having 4 total processors.
These extra cores are also called virtual or logical cores. Obviously, a logical core will never be equivalent to a physical processor. Roughly, having a logical core is equivalent to having an extra physical core.
Turbo: CPU frequencies are not fixed but dynamic. These will oscillate between different values based on load and temperature. When a processor is not used, the frequencies can drop below Gigahertz. During use, the processor tries to reach the maximum frequency as quickly as possible, to finish the job as quickly as possible. If time or temperature parameters are exceeded, the frequency will be lowered to lower values, more bearable for continuous use. The processors also have different turbo values based on how many cores are under load. Straining a single core allows you to reach higher frequencies than asking for work from all cores.
IPC: Instructions for Clock are a hidden parameter, but it is good to know that they exist. They indicate how many instructions the processor is able to make in a clock cycle. This value changes from architecture to architecture. A processor with an IPC of 2, is able to carry out to 1Ghz the same work as a processor with 1 IPC to 2Ghz.
The market for "consumer" processors is a duopoly, with Intel ed I HAVE D to contend for the market. Intel designs and builds all its chips internally. AMD is a factory with no factory, so you only design the processors, leaving the production to external companies, such as GlobalFoundries o TSMC
Intel produces a disproportionate amount of processors, which are grouped into these categories: Celeron, Pentium Gold, Core i3, Core i5, Core i7, Core i9. Added to these are the Xeon cores, professional variants with multiple security-oriented and virtualization features.
How to choose
The starting points are two and are diametrically opposed. If you start with a fixed budget, you have to try to buy the best processor that money allows. On the contrary, if you start with a goal to be achieved, you must find the component with the best quality / price ratio that meets my requirements.
What you have to do avoid when building a PC, is that the system suffer from a bottleneck by one of its main components. The CPU and the GPU work together. The CPU prepares the frames and the GPU processes them. Too slow a processor, it might not pass data fast enough to the GPU that it would not be used to the maximum.
If you want to play "normally", which means resolutions between the 1920 × 1080 and the 4K with framerate between the 60 and the 75fps, processors of the 150-200 € band are more than enough. To go on higher framerates with AAA games, it will be necessary to focus on CPUs capable of reaching the highest possible frequencies, as the preparation of game frames is a sequential task and benefits greatly from the performance of individual cores. If you want to stream while playing, instead, you need to buy processors with many more cores, so that there are enough for the game and the stream to be encoded at the same time. If you want to use professional rendering or CAD programs, you need to know which processors can best meet the needs of the individual program, there is no real ace.
Tips for shopping
Currently, what are the best choices for the various market segments? To avoid searching for a compatible motherboard elsewhere, all processors are recommended with a motherboard.
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Price: EUR 47,99
Price: EUR 57,21From: EUR 85,00
The AMD Athlon 200GE, with 2 core with SMT technology, for 4 total threads, is the most economic offer at the moment, able however to offer dignified performances for all the basic operations. If you want an office PC or a miniPC multimedia center (HTPC), it's a great choice.
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This Intel processor offers 4 fast processors, capable of managing the 99% of video games without major problems. Games like Anthem or Assassin's Creed Odyssey will push him to the limit, so if you want to stay on top of the pushed or massively multiplayer AAA open world game, head to the next band.
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Price: EUR 148,21From: EUR 209,90
Price: EUR 90,16
Price: EUR 165,08
If you want to play and work equally without spending a lot of money on your computer, these two combos are great. Ryzen offers 6 core with 12 total threads and the ability to be overclocked to achieve the performance of its big brother. The intel only offers 6 core / 6 total threads and 0 overclock, so in highly parallel jobs it loses some of its way, but in games it has generally better performances.
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Price: EUR 399,99From: EUR 439,99
Price: EUR 260,99
Processor with 8 physical cores, without HT. With overclocking it can reach and exceed 5Ghz. This guarantees optimal performance with every game and is a must if you want to reach high framerates in each title and give vent to the most powerful GPUs in each scenario. Having a generous number of cores allows the product to shine even in production or by streaming. The i5 9600k has the same overclocking potential, but with 2 core less it will weigh less on your wallet. If you want to overclock, you need to invest in a good sink.
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Price: EUR 219,99From: EUR 349,90
Price: EUR 87,49From: EUR 129,00
8 core with 16 total threads at an extremely competitive price. In game you will get the same performances as a Ryzen 5 2600, but its extra cores are very useful if you want to stream software encoders or work with graphics and rendering programs.
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Price: EUR 499,99From: EUR 549,99
CPU with 8 core and 16 thread, but with the ability to push them to 5Ghz and beyond. The energy consumption and heat released are considerable, but currently it is the most performing processor in the consumer field and it is even better than many other HEDT components in many professional workloads, thanks to its high frequencies and extremely low core latency.