The processor is the brain of the computer. From its choice directly depends on the speed of applications and the operating system.
But how to choose the right processor for your computer?
Choose the type of connector (socket). To connect to the motherboard it is necessary that both devices have the same socket. If you buy a processor for a finished computer - find out the socket of the motherboard. This can be done using software (for example, EVEREST). Either open the cover of the system unit, write down the name of the motherboard and find its specification on the manufacturer's website.
In general, office computers usually use a socket LGA1156, for home - LGA1366, for gaming - LGA2011.
Choose the frequency. In fact, the performance of the processor is determined not by the frequency, but by the product of the frequency and number of cores. This means that a processor with 4 cores and 2 GHz will be much more powerful than a processor with 2 cores and a frequency of 3 GHz.
For an office computer, the best option is a dual-core processor with a frequency of 2.5 GHz, for home and gaming computers it is better to choose quad-core processors.
Do not forget to buy a cooler for the CPU (fan). It is installed over the processor and tightly pressed against it to prevent overheating.