A standard computer needs at least 1 gigahertz or greater for the Windows 8.1 operating system. A computer that will be used for gaming may need 2 to 3 gigahertz to run games, according to Riot Games.
Gigahertz is also written as GHz, and it is a measure of roughly how fast a central processing unit (CPU) can do basic processing in a second. Gigahertz gives a rough estimate and is not an exact rate. When a CPU has a high gigahertz, it needs a good cooling system because the higher the GHz, the more energy it uses, and it will also heat up faster.