FPS stays above 100 without Vsync, but drops under 60 when using Vsync
FPS stays above 100 without Vsync, but drops under 60 when using Vsync
GTX 970, I5 4690K @ 4ghz, 16GB DDR3 RAM, SSD, 60hz monitor Windows 10.
If I'm running a game with uncapped framerate and maintaining at least 100FPS, then turning on Vsync and setting a 60FPS lock causes my frame rate to fluctuate between 55-59 and then jump back up to 60, leading to stutters. I've experimented with RTSS, Nvidia Control Panel adjustments, and other settings, but the issue varies from game to game. If I can stay above 100FPS without Vsync, why does it drop below 60 when using Vsync?
I have some ideas about this, such as because the GPU can work faster than the refresh rate, VSync might make the GPU slow down at certain moments and those pauses can lead to issues when it needs to increase speed again.
If you're using VSync to prevent tearing, a solution I recommend for Windows 10 is to play games in either windowed or borderless mode. This forces triple buffering plus Vsync on all windows, letting the GPU render quickly but only showing the most recent frame.
FPS doesn't always indicate consistent frame times. It's possible to achieve 100 FPS if most frames occur within the first 99 milliseconds of sampling, with the final frame accounting for the remaining time. The system might occasionally record frame durations between 17-18 milliseconds per frame, yet still register a Vsync hold.
I have some ideas about this, such as because the GPU can work faster than the refresh rate, VSync might make the GPU slow down at certain moments, leading to interruptions when it needs to increase speed again. If you're using VSync to prevent tearing, a suggested solution on Windows 10 is to play games in either windowed or borderless mode. This forces triple buffering plus Vsync across all windows, enabling the GPU to render quickly but only showing the most recent frame.