VSync was the original synchronization technology for GPUs, video games and monitors. Despite new options like G-Sync or FreeSync, VSync remains an essential option for many players. But what does it do and is it still worth using?
Let's take a closer look at what VSync is and why it matters.
What is VSync technology?
VSync, or vertical sync, is a graphics technology that synchronizes the frame rate of a game and the refresh rate of a game monitor. This technology was first developed by GPU manufacturers and was one way to deal with screen tearing. Your screen shows parts of several frames at once. This can result in something like the image above, where the display appears to be split along a line, usually horizontally. Tearing occurs when the monitor's refresh rate (how often it is refreshed per second) is out of sync with the frames per second.
Screen tears can occur at any time, although they are most common in fast motion, especially when a game is running at a higher frame rate than the monitor can handle, or when the frame rate changes dramatically and the monitor cannot keep up. This is particularly noticeable in fast games with vertical picture elements such as trees, entrances or buildings. When this happens, these lines are clearly not properly aligned, which can interrupt immersion and make a nice game look pretty ugly.
VSync takes a few steps to fix this. First, the frame rate output by the graphics card is limited to the refresh rate of the monitor (60 Hz unless you have a monitor with a high refresh rate), making it easier to avoid higher FPS than the monitor can handle.
This is done by preventing the GPU from doing anything to the display memory until the monitor has completed its current update cycle – and effectively not entering any further information until it is ready. With a combination of double buffering and page turning, VSync does not synchronize the drawing of frames on the display until an update cycle is complete. So you should never see tears when VSync is activated.
Does it make a big difference?
VSync only helps tearing the screen, and this only really happens when the FPS are limited when needed. If your monitor can't keep up with the FPS of a particular game, VSync can make a big difference.
However, VSync cannot improve your resolution, colors, or brightness levels like HDR. It is a preventive technology that focuses on stopping a specific problem rather than making improvements. It also tends to degrade performance.
Forcing frames to render fully before viewing can affect your frame rate. At best, your frame rate is limited to the refresh rate of your ad. For some games where higher FPS can result in reduced entry delay, this can also affect your competitive performance.
What do I need to activate VSync technology?
You don't need a specific monitor to use VSync. It works with all types of displays. You need a graphics card that supports this, but the latest generations support it across the range. VSync has been around for many years, and both Nvidia and AMD have options to enable the setting in their drivers for all games.
However, if you prefer to do this on a single game basis, most games offer this option as a toggle option in the graphics settings menu.
Does VSync have any problems?
VSync is far from a perfect solution and can negatively impact your gaming experience, even if it is useful and works as intended. If a monitor and a game are having trouble syncing, VSync can drop the frame rate significantly to find a point where they can. This can lead to entry delays and stuttering, which further worsens the gaming experience. Screen tears are most noticeable in fast-paced games like shooters and fighters, but can affect all types of games, regardless of genre.
If you take this type of game seriously, it may not be worthwhile to activate VSync. There is another setting called triple buffering that can help alleviate some of VSync's problems. However, it offers no guarantee.
What are Adaptive VSync and FastSync?
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It gets a little more complicated here. GPU companies were aware of the potential issues of VSync when first released and have been trying to develop improved versions since then. For this reason, various synchronization options may appear when you access the GPU Control Panel. More advanced forms of VSync include:
AdaptiveSync: This is an Nvidia enhancement that monitors the monitor's maximum refresh rate. If the game's FPS is equal to or higher than the update, VSync is enabled. If the FPS falls below, it is disabled, which prevents the occurrence of problems with the input delay.
FastSync: FastSync is an advanced form of Nvidia's advanced synchronization that enables VSync when needed and adds automatic triple buffering to always choose the best possible frame data. Using it requires a lot of power, but it also helps fix many VSync problems.
Improved synchronization: Enhanced Sync is AMD's version of AdvancedSync. VSync is disabled when the frame rate drops below a monitor's refresh rate to avoid related problems.
Is VSync better than G-Sync or FreeSync?
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To improve the synchronization technologies, Nvidia developed G-Sync and AMD, FreeSync. Both GPU technologies carefully synchronize update rates and other image data directly with the frame rate of your graphics card in order to achieve a smoother and sharper image without the potential problems of VSync. Think of it as the ultimate form of VSync – and it's worth activating when you have it.
The trick is that you need both a graphics card that supports the technology and a monitor that also supports it. Nowadays you can find many excellent monitors that are compatible with G-Sync or FreeSync. There are some who support both to a limited extent. However, since they are competing technologies, you will usually find that monitors support one or the other. That said, you need to make sure you get a monitor that matches your GPU technology, and vice versa.
VSync is a viable alternative, but both Freesync and G-Sync are more powerful and should be used instead if you can.