If you are an intense gamer, you may have come across a confusing option in graphics settings. It’s called VSync, and it very hard to guess what it actually does and why this option is provided.
Short Description: VSync stands for Vertical synchronization. It forces the graphics processor’s frames to match (or sync) with the refresh rate of the monitor. This synchronization eliminates frame rate stuttering and screen tearing to deliver a smooth, uninterrupted gaming experience.
But how does it work? What are its benefits? Should you turn this option on or off? To answer these questions, we need to learn more about VSync. Let’s starts with the basics.
Why Is VSync Required?
First, we need to understand how graphics are processed on a desktop or laptop. Your computer renders graphics to the screen using either an integrated graphic (CPU) or a dedicated graphics card (GPU).
In both cases, the processor ‘paints’ visuals on the monitor. The article you are reading at this moment is drawn by your graphics processor. When you play a game or watch a movie, your graphics processor is commanded to render a 3D image (full drawing or frame) as quickly as possible. It creates multiple frames per second (FPS).
These frames are then sent to the monitor to process. This results in a rapid slideshow of the frames, which gives the appearance of animation, similar to a flipbook. The higher the FPS your graphics can produce, the smoother your gaming experience.
Even if you are not playing games or watching videos, the display still needs to update so you can see what you are typing, where the mouse cursor moves, and so on.
The monitor always tries to keep up with the frames that your graphics processor outputs every second. The maximum number of frames a monitor can display in one second is called its refresh rate, which is usually measured in the unit of Hertz (Hz). For example, a 60 Hz monitor can display up to 60 FPS.
Now that you understand how images are rendered on the screen, here comes the actual problem. The issue arises when the graphics processor starts producing more frames than the monitor can handle; for instance, 90 FPS on a 60 Hz monitor.
In this case, the monitor struggles to keep up with the flow and results in synchronization disorder between two frames. This causes ‘screen tearing,’ where the picture appears to be cut in half.
Screen tearing as seen in Battlefield 3 | Image credit: NVIDIA
The screen tearing is mostly visible when the camera moves horizontally. But since pictures are registered vertically, you won’t see tearing up and down the screen. It is still very annoying, and it degrades the overall gaming experience.
What’s the Solution?
The obvious solution is to buy a monitor capable of displaying high frame rates, but not everyone can afford that.
That’s where VSync comes in handy. It fixes the syncing issue by matching the graphics processor’s frames with the monitor’s refresh rate. To do this, VSync freezes the game engine or buffers the frames until the screen is ready to show the next frame.
In other words, VSync brings your graphics processor down to the same level as your monitor, allowing them to work better in unison with fine-tuned cohesion. When correctly implemented, it completely eliminates the screen tearing and promotes more fluid, smoother gameplay.
VSync can also be useful in other applications, specifically in old games, where the processor overpowers the graphical requirement. Since modern CPUs/GPUs are too powerful to run vintage games, they render old scenes at very high frame rates.
This could cause the processor to overheat, as it works super fast to create hundreds of frames per second. VSync can handle this situation by capping the FPS to the monitor’s refresh rate and thus unloading the extra strain on the graphic processor.
Enabling VSync introduces some issue of its own —
When GPU stops transmitting more frames to the monitor, your inputs, such as mouse clicks and key-presses, might get slightly delayed. These delays are often not noticeable, but if you are playing games that require quick reflexes, it could simply pull you out of the immersion.
Also, when you view scenes that require excessive graphics resources and the frame rate comes down below the refresh rate, the graphics processor brings it down further to sync with the preferences of the monitor. At such intense moments, a bigger drop in frames (and thus more delayed response) is registered.
Various methods, such as triple buffering, have been developed to eliminate this issue, but it may not be accessible to everyone. There are also a few other techniques to help you minimize such lags, but you should be aware that enabling VSync could make your actions less responsive than before.
VSync can also result in artifacts in movies and videos because they are usually recorded at 24-30 FPS, significantly lower than the conventional monitor frame rates. When such movies are played on a 60 Hz monitor, the video player misses the monitor deadline frequently, causing interceding frames to display slightly faster than usual. This results in a judder-like effect.
Modern Forms Of VSync
VSync is over a decade-old technique. In recent years, graphics manufactures have developed more effective methods that deal with the limitations of VSync. The most popular ones are —
Smooth VSync is specially designed by NVIDIA to minimize stutter when VSync is enabled and SLI (scalable link interface) is active. SLI is a parallel processing program for graphics, meant to enhance processing power.
Unlike conventional VSync, which forces the frame rates to rapidly oscillate between the refresh rate and half the refresh rate (such as between 60 Hz and 30 Hz), smooth VSync locks into the most sustainable frame rate of your game. It only increases the frame rate when the game performance exceeds the monitor’s rate.
Although smooth VSync reduces your game’s average frame rate, it improves and streamlines the overall visual experience.
2 Adaptive VSync
Developed by NVIDIA, adaptive VSync allows you to render frames (in a smart way) using the NVIDIA Control Panel tool. It is exclusively available to GPUs running a GT 600-series NVIDIA graphics or newer.
Adaptive VSync deals with screen tearing as well as frame rate stuttering. It enables VSync when the frame rate exceeds the monitor’s refresh rate (to eliminate tearing) and disables it when FPS drops below the monitor’s refresh rate (to minimize stuttering).
G-Sync is another proprietary adaptive synchronization method built by NVIDIA to eliminate screen tearing. It allows the monitor’s refresh rate to adapt to the graphics card’s frame rate (rather than the graphic processor adapting to the monitor).
In order for a monitor to use G-Sync, it must be equipped with a G-Sync technology distributed by NVIDIA. The company works with most LCD panel manufacturers to bring a wide range of high-speed panels (from 75 Hz to 360 Hz) to market.
NVIDIA claims that devices with G-Sync technology deliver lifelike HDR, cinematic color, stunning contrast, and ultra-low latency gameplay with no stuttering, tearing, or input lag.
In 2015, AMD released its own adaptive synchronization technology for LCD, FreeSync, to compete against NVIDIA’s G-Sync. It is free to use, royalty-free, and has no performance penalty.
Image credit: AMD
FreeSync works by dynamically adapting the monitor’s refresh rate to variable frame rates. More specifically, the monitor keeps showing the currently received picture until a new frame is delivered to the graphic card’s frame buffer. Then, the new picture is transported immediately.
This simple technique provides an extremely low monitor latency and a slutter-free viewing experience. It also improves battery life by decreasing the panel’s refresh rate when not receiving new images.
The standard supports refresh rates between 9 Hz and 240 Hz. And since it can be enabled automatically via plug-and-play, it is transparent to the end-user and operating system.
5. Enhanced Sync
Instead of locking the frame rate maximum to the monitor’s display refresh rate, AMD’s Enhanced Sync technology uncaps the frame rate to decrease latency in exchange for some mild tearing.
When the graphics card cannot output frames at the same speed as the monitor’s refresh rate, this method prioritizes reduced stutter over eliminating tearing. Although it doesn’t completely fix the problems associated with VSync, it does improve the performance capability and consistency. Furthermore, it works with any display, whether it supports FreeSync or not.
Should You Turn It On or Off?
The answer to this question depends on preference and specific case by case scenarios.
If your GPU produces more frames than your monitor can handle, it may cause screen tearing and excess heat. In this case, you need to enable VSync either via your GPU settings or program software.
However, if your monitor can display more frames than the GPU is generating, there is little reason to have VSync enabled.
You should also disable it when your game arrives at a graphically intense climax and the frame rate drops below the screen’s refresh rate. This is because in such cases, VSync automatically attempts to match that sudden change, resulting in performance lag.
Turning VSync on and off is very simple — Open the NVIDIA control panel, select Manage 3D Settings, and under the Global Setting tab, you will find a list of features. Scroll down to Vertical Sync and select On/Adaptive. That’s it.
If you are using an AMD processor, you can find similar options in Radeon settings. There is also an option to apply your preferences to individual games.
Now that you know the advantages and disadvantages of VSync and how easy it is to turn it on or off, it is worth trying both options. You should also check whether your graphics processor has additional features. Adaptive VSync, for example, is designed to deliver the best of both worlds.
Frequently Asked Questions
Does VSync improve screen resolution?
VSync neither affects the resolution nor color/brightness levels of the monitor. It is only designed to eliminate screen tearing and provide smooth viewing and gaming experience.
Can VSync increase FPS?
VSync cannot increase the monitor’s refresh rate or FPS. In fact, it does the opposite: it caps the FPS to the monitor refresh rate and reduces the strain on GPU.
Is VSync good for Fortnite?
Fortnite is a fast-paced, action-packed game. If you have a standard 60 Hz monitor, enabling VSync could significantly improve your gaming experience (by synchronizing the monitor and graphics card refresh cycles). The same is true for other popular games such as Minecraft, Overwatch, and Quake Champions.
How much lag does VSync add?
In general, enabling VSync results in higher input latency, and disabling it results in lower input latency. According to a study (performed on three games: Super Meat Body, Left 4 Dead 2, and Sleeping Dogs), turning on VSync in fullscreen without locking the FPS has input latency as much as 7.5 frames. Whereas, turning off VSync in fullscreen without locking the frame rate has an input latency of only 1.33 frames.