MilkyWayPiano wrote: ā27 May 2026, 17:22
jorimt wrote: ā30 Jun 2017, 16:46
Also, don't get caught on perfect frametime output, at least if it is at or fluctuating above (lower frametimes) your target framerate. Let's say you have a 60 FPS in-game limit, and you watch the frametime meter fluctuate between 16.6ms (the target frametime), and, say, 12ms, 14ms, 8ms, 16.6ms, etc. Frametime is separate from scanout time. Frametime dictates how long it takes a frame to be rendered and ready for scanning in. It could theoretically sit there forever until the display decides to refresh and start scanning it in.
In other words, as long as the fluctuating frametimes you are seeing are lower than your set framerate limit, they will be displayed in the desired intervals regardless if they finish earlier or not. The only thing lower fluctuating frametimes with in-game limiters can cause is less input lag.
When capped at 60 FPS, is it a problem if the frametime fluctuated above 16.6 ms? In Hogwarts Legacy, I've noticed frametimes north of 20 ms when capped at 60 fps.
Would fluctuating frametimes result in tiny hitching or microstutters when panning the camera in-game? I notice this in every game I play. I always assumed it was because of fluctuating frametimes.
Yes. And it depends on the sync technology and refresh rate in use, as well as whether you're using RTSS or in-game.
VSYNC ON - If a frame queue is used and the VSYNC ON setting is used, frametime spikes are usually hidden by VSYNC ON if the frametime spike is less than native-Hz time. The hitching does not become visible at 60-120Hz, but may become visible at 240Hz because 4ms = 1/240sec = frame rounds off to next refresh cycle. In this case, either cap works.
VRR - If VRR is used, a 25% frametime spike can sometimes show as minor unsmoothness, much more noticeable if strobed. In this case, RTSS cap will be more accurate.
External capping (RTSS) usually has less hitching than in-game capping. RTSS utilizes microsecond-accurate frame rate capping, while ingame cap fluctuates much more (averaging-based frame rate cap), so if you want to make it more glassfloor during VRR and high-Hz operation, use an external RTSS cap. You can also attempt RTSS' Scanline Sync feature too, if you want a somewhat lower latency method (more complex).
I've seen hitching disappear with some good in-game caps, but not all in-game caps are accurate. If you prioritize the complete disappearance of hitching, use an RTSS cap, and cap below your average frame rate, and it can go nearly hitching-less (except for things like disk load stutters and shader compile stutters).