For those who are passionate about PC games or 3D graphics editing, the phrase VSync is undoubtedly not too strange when it frequently appears in the video settings. But not everyone understands what VSync is, what its functions are, and how it does work? Should it be turned on or off in Game Settings for the best experience?
To answer these questions, this article will explain the key points of this term and why you should or should not enable VSync.
What is VSync?
VSync stands for Vertical Synchronization. In other words, VSync means synchronizing the FPS (frames per second) of the games with the monitor's Refresh Rate.
The term Vertical Synchronization was born since the use of older CRT monitors that were designed to refresh the display periodically. Physically, today's LCDs don't have that feature. However, they still have a response time (time response rating - LCDs are now typically 5ms, for example) - which shows how long pixels change from white to black.
To begin with, let's take a look at how your computer handles graphics. Desktops or laptops both have a way of displaying pictures on the screen. This can be an integrated graphics card in the processor or a discrete graphics card. The main job of the graphics card is to "paint" the image onto the screen.
When you ask the graphics card to draw a 3D scene, it will process the full picture, or "frame", as quickly as possible. Then it puts these frames on the screen for processing, creating a slideshow effect that quickly causes an animated appearance. The speed at which the GPU can output frames is called "Frame Per Second" (the number of frames displayed per second), abbreviated as FPS. The lower this number is, the weaker your gaming rig is and vice versa.
Your monitor tries to keep up with the number of frames that modern graphics cards produce. The maximum number of frames it can display is confirmed in the refresh rate, usually defined in frequency or "Hz". When you play games with the screen refresh rate of 60Hz (it is loaded with 60 images per second), and the FPS exceeds that number, it means that they're not synchronized. That will lead to the phenomenon of "tearing" or "ghosting".
It won't be easy to notice this if you play games at low FPS, but it will be easier to see in high-speed games or high FPS.
When "conflict" occurs
The problem occurs when your graphics card outputs more frames than the actual processing speed of the monitor, such as 100FPS on a 60Hz monitor. Your monitor tries to keep up with the "flow" and ends up getting out of sync between the two frames. This is called "screen tearing", where the image is "cut in half".
This is where VSync plays its role. VSync aims to match the frame's graphics card to the monitor's refresh rate to fix any synchronization issues. This is usually done by freezing the game engine or buffering frames until the monitor is ready to output the next frame.
Pros of VSync
As we stated above, VSync is worth it if you have trouble with your display. This will bring your graphics card down to the level of the monitor and allow them to perform better, thus eliminating screen tearing.
Additionally, it's also valuable for applications (like old games) where your graphics card "overwhelms" your graphics needs. Because the GPU goes as fast as possible, rendering old footage can result in extremely high frame rates. This can cause your graphics card to overheat as it outputs frames at breakneck speeds. Enabling VSync will limit the screen refresh rate and prevent undue strain on the GPU.
Cons of VSync
VSync forces the graphics card to wait for the monitor until it is ready; this can cause problems. You may find that input, such as keypresses and mouse clicks, is delayed slightly. It can be considered a disadvantage in games that require quick reactions. There are several technologies developed for VSync that help reduce this lag. However, always keep in mind that if you enable VSync, you'll notice that your in-game actions are less responsive than before.
VSync is excellent when the frame rate exceeds the monitor's refresh rate. However, if it comes to an "intense" time when the frame rate drops below the refresh rate, the graphics card will "drop" it down to fit the screen. Technologies like triple-buffering support can help prevent this, but it's not an option everyone has access to.
When should I activate VSync?
If you notice tearing or blurring appearing during game sessions, it's best to turn it on. This phenomenon is caused by GPU sending too many images before the monitor can process them. Enabling V-sync eliminates it by forcing the GPU to stop sending new frames to the screen before the monitor can process it.
In other words, V-sync will synchronize the game's FPS so that it is equal to the screen's refresh rate.
In general, if your graphics card displays more frames than the monitor can handle, it can cause overheating and tearing. Try enabling VSync with the software or setting the graphics card to smooth things out.
I would like to conclude: Turning on or off V-sync depends on the user's perception, the refresh rate of the screen, and the game's configuration. Suppose your device has a superior configuration and the FPS is more than 100. In that case, V-sync should be turned on for a smoother experience. If the configuration is weak to bring the game to an FPS of 60, you should turn off V-sync.
Now, you know how easy it is to turn VSync on and off, you should try both ways. When you understand more about how VSync works, you can make a more straightforward decision about whether to enable it. You also should check if your graphics card package comes with additional enhancements, for example, Nvidia's Adaptive VSync.