What does V-Sync actually do to your PC's frames per second?

If you've ever fiddled with graphics settings, you've probably come across VSync. Short for vertical synchronization, it can help eliminate screen tearing, which is when the display shows pieces of two different frames at once. Although turning VSync on can stabilize your frame rate, it can lead to other issues, so it's good to understand it before diving in.

You probably know that a game's frame rate indicates how many frames your GPU renders each second. Your monitor's refresh rate is the number of times per second it can display a new image. Ideally, those rates work together in a way that is efficient, responsive and creates a stable illusion of motion.

But in practice, that isn't always the case. If your graphics card renders a game at 100 FPS but your monitor only refreshes at 60 Hz, you might see screen tearing. In practice, that can look like a horizontal split where parts of the image are misaligned. If you see that, VSync can be a handy tool.

VSync tries to fix screen tearing by making the GPU wait for the monitor's refresh cycle before firing the next frame. So, on a 60Hz display, the game would typically render around 60 frames per second. On a 144Hz display, it would be 144 FPS. Even if your graphics card can handle more than that, VSync makes it wait until the monitor can display the next frame. As a bonus, that can mean your GPU isn't working as hard, which could reduce power consumption and heat.

In a best-case scenario, VSync delivers a clean, smooth flow of frames. Everything on-screen feels stable: character movement is fluid, and the game world looks consistent. But as with most PC gaming settings, there are trade-offs — and probably some trial and error involved in finding the best balance.

Eliminating screen tearing can have unwanted side effects. One case is when the GPU's frames can't keep up with the monitor's refresh rate. In that case, the game might suddenly feel more like 30 FPS than 60 FPS. (The exact result depends on your setup.) At worst, you'll see stuttering that will make the problem you were trying to solve — screen tearing — seem minor.

Another common VSync problem is input lag. When it's turned on, frames have a strict delivery schedule, which could lead to a slight delay between your input and the result you see on screen. In, say, a slow-paced adventure game, you might not even notice. But in a competitive shooter that delay can make everything feel heavy and sluggish.

If you don't notice any screen tearing, leave VSync off. And even if you do see tearing, there might be better options.