GameSwift 

GameSwift is a simple tool meant to make games run smoother on your computer. In other words, it tweaks and optimizes your system so that you enjoy a better game playing experience, one that is free from freezes, slowdowns, and other annoying issues.

As far as I can tell, the main methods used by GameSwift to achieve its purpose and make your computer behave better when running games is based on changing the priority level of the CPU so that applications running in full screen, such as games, are given more power and faster access to the CPU cores. An increase of the well-known FPS parameter (the frames per second) of the games' graphics is also supposedly a result of letting GameSwift optimize your system for game running, but I'm not sure how GameSwift achieves this too. Other performed changes are turning off unnecessary animations or modifications in how the memory swap file is used by games and programs.

GameSwift is very simple to use and straightforward. Just install it, run it, check if it correctly detected your OS version and CPU type, and press the “Optimize” button. Then you may let the program do its optimization job. The actual results, the changes in gaming performance, may vary depending of multiple factors. There are decent chances that GameSwift will indeed make a difference and your games will run in a smoother manner on your PC from now on.

To sum it all up, GameSwift is an interesting tool that might represent a decent choice if you're looking to improve the gaming performance of your computer without spending much money on new hardware.