By synchronizing the refresh rate of your monitor with your graphics card, the monitor can draw a new frame whenever it is ready, without introducing stutters, screen tearing, or latency.
NVIDIA G-Sync is a technology licensed by NVIDIA to companies that manufacture the best computer monitors and laptop displays. Basically, it allows the monitor and GPU to communicate with each other perfectly, resulting in silky smooth, tear-free gaming. Every frame output by the GPU is drawn by the display, and the variable refresh rate ensures no tears during gameplay. It is not, however, activated automatically when you connect a G-Sync display. There is some minor setup required, but the good news is that you won't need to install any additional software as long as you've already installed drivers for your NVIDIA GPU.
But when you’re building a PCs, minor mismatched is inevitable. This can make synchronizing the frame rates of the hardware producing the images and the refresh rate of the displays displaying those images difficult. Some of the most annoying graphical issues in PC gaming can be found in the space between those two numbers. When the frame rate exceeds the refresh rate of your monitor, you're likely to see tearing and artifacting—your monitor is caught trying to display multiple frames at the same time, resulting in pieces of each frame overlapping. Stuttering and slowdown occur when the frame rate suddenly drops into the gutter. It's a problem that has afflicted PC gaming since its inception.
The solution of the problem we mentioned before is V-Sync. V-Synch effectively limits your game's frame rate to the refresh rate of your display. This ensures that a frame is fully displayed and the refresh cycle is completed before displaying the next frame, effectively eliminating tearing. However, v-sync has some drawbacks. The most notable is that it can increase input lag, which can be extremely problematic in games requiring fast reactions such as competitive first-person shooters and fighting games. V-sync still allows for some tearing when frame rates jump quickly between rates below a monitor's refresh rate, such as between 25 and 50fps on a 60Hz monitor.
Fortunately, modern solutions have mitigated some of V-Sync. Variable Refresh Rate or VRR is intended to eliminate tearing at all frame rates while minimizing input lag. It accomplishes this by dynamically syncing the refresh rate of your display to the frame rate of your hardware (assuming it is at or below the display's native refresh rate). This ensures that, even if the frame rate changes quickly, your TV or monitor will always display one complete frame before drawing in the next.
G-Sync is Nvidia's proprietary VRR technology. The best and most efficient implementation is achieved by incorporating specific hardware, in the form of a processor module in the monitor itself, which handles the heavy lifting of adjusting the refresh rate on the fly. However, Nvidia has certified some monitors that lack the dedicated G-Sync processor as G-Sync-compatible, and some monitors that aren't certified will still work with G-Sync (albeit with mixed results). AMD's VRR solution, FreeSync, is based on an open standard known as VESA Adaptive-Sync. Nvidia has also begun to support VESA Adaptive-Sync under the label "G-Sync compatible" since 2019.
If you’re going to use G-Sync first of all you need figuring out does your monitor support G-Sync or not, you can check the list here. The list is organized by default according to Nvidia's three-tier classification system: G-Sync Ultimate and G-Sync monitors include dedicated processors to provide the best experience, while G-Sync-compatible monitors lack onboard hardware but have been validated by Nvidia's engineers to provide solid VRR.
To set up G-SYNC after ensuring that your monitor is connected to the correct port, right-click the Nvidia icon in your System Tray and select Nvidia Control Panel. You can also open it by right-clicking on the desktop. Locate the Display header on the left in the Nvidia Control Panel and select the Set-up G-Sync entry in the sub-menu. Select Enable G-Sync, G-Sync Compatible, and then specify whether you want it enabled for full-screen mode only or for both full-screen and windowed modes. If you have multiple displays, you must choose which one to enable G-Sync on. Depending on your monitor, you may also be able to toggle specific settings for the selected display on or off. Close Control Panel by clicking Apply at the bottom.
That’s basically how to Set Up Nvidia G-Sync Properly. To see if G-Sync is working properly, download Nvidia's GeForce Tech Demos. You may want to tweak settings in individual games for the best results, including running them in exclusive full screen mode whenever possible. Your primary goal should be to keep your frame rate within the refresh rate range that your monitor supports for G-Sync compatibility. If you frequently exceed the maximum frame rate, consider limiting the maximum frame rate in your game's graphics/display menu. If, on the other hand, you frequently fall below the lowest supported refresh rate threshold, you may want to reduce some of your game's graphics settings to consistently yield higher FPS.