Apart from the hardware, some people do not want to spend some more money on the computer but still need to improve the overall performance of the game's they used to play . So there is a widely used third party program called "Game Booster" which can help you without investing some extra cash.
Game Booster is designed and developed by a company called iobit.This Application is very useful on older computers that will have basic configuration that have a hard time with the requirements of the game that is being played. The Game booster is available in free & paid version but the free version is good enough to run in the computer if you have some extra cash to spare then you can buy the program instead of buying a new hardware for the computer.
Game Booster have the capacity to optimize the computer before you load the game by selecting which programs to be stopped so you can utilize more RAM and you can reduce the load on the CPU. In case If you are using a brand new computer and try to use this program, the pro gramme will have not have much effect unless you have so many useless application's on your computer that may consumes all the RAM and CPU usage. This application helps in de-fragmenting the hard drive to improve the overall loading performance in games.
Besides the Game Booster, which makes the task's easier to improve the game performance, you can use the Task Manager, the task manager in Windows can be accessed by pressing Ctr - Alt - Del or by right clicking on your taskbar and selecting Task Manager. The Task Manager should be used by advanced user's as if you try to kill or stop some of the very important process that is running behind the Operating system, it may make the computer unstable temporarily or even carsh.