Why 200+ frames per second at 60 hertz prevents screen tearing?
Why 200+ frames per second at 60 hertz prevents screen tearing?
In games like Left 4 Dead, on a 60 Hz monitor with FPS not capped and usually above 200, screen tearing and stuttering disappear completely every time and appear perfectly smooth. This experience is much better than using VSync with a 60 fps limit. Many people claim uncapped FPS causes more tearing, but it doesn’t seem to be true when the frame rate is high enough. Who can clarify why this happens?
For quick reference, contemporary displays rely on signaling methods similar to those used in CRTs. The system comprises three primary components:
The actual pixel data
H-Blank interval, during which the electron gun stops moving to position itself at the left edge of the screen (beginning of a new line)
V-Blank interval, when the electron gun halts to move to the top of the screen (start of a new frame)
V-Sync ensures the video card delays rendering the current frame until the next V-Blank period. This can lead to stuttering, especially if the card takes longer to process the next frame within the 60Hz cycle.
With an unconstrained frame rate, you're observing the most up-to-date information. The absence of noticeable tearing might stem from the minimal frame differences being perceptible, and this also hinges on the timing of frame rendering.
Another factor contributing to stuttering is frame pacing. A standard frame rate only indicates the number of frames rendered per second; it doesn't reveal irregularities in timing. There can be moments where frames are rendered in quick succession followed by longer gaps, such as 16ms pacing equating to 60 FPS or half the frames in 8ms and the other half in 33ms.