Originally Posted by Blameless
Only if you insist on using vsync in games that do not have good triple buffering implementations will you need to push a constant 120+ fps.
Good to ponder the angles --
The "need to" question is different from "is there a benefit?" and is also different from "What's needed to max-out a 120Hz monitor?"
Otherwise, the extra Hz can benefit at any frame rate.
You do get less input lag at any framerates. However, from a "achieving the maximum possible image fluidity" perspective (zero visible microstutters, zero tearing, etc)
To my eyes, VSYNC ON (both double and good/bad triple buffer versions), Adaptive VSYNC *and* VSYNC OFF are generally not maximized at less than triple-digit framerates.
Also, having framerates far in excess of Hz is also a benefit for VSYNC-OFF. You've got fresher frames (less input lag) and you've got smaller-offset tearlines. During 300fps, having 300 tiny-offset tearlines can be harder to see than just 100 large-offset tearlines. Eventually at "insane" framerates, offsets are so tiny (a few pixels, or even just a pixel), that VSYNC OFF looks as fluid as good as framerate-locked VSYNC ON, but it requires several hundreds of frames per second for that to happen. A great example is running very old Source engine game with VSYNC OFF, on a Geforce 780 or Titan -- that runs at several hundreds of frames per second. Or even running an old copy of QuakeWorld, etc. Some people like me, are sensitive to tearing even at triple-digit framerates (200fps, 300fps) and tearing just gradually fades in intensity the higher the framerate you go (due to the shrinking offset of tearlines). And also avoiding harmonics between framerate and Hz, so you want to avoid setting fps_max values to those harmonics. (e.g. two annoyingly stationary tearlines can occur during 240fps@120Hz).
For theoretical maximized human-visible benefits, if you're targetting the top (the cieling of what's human-benefittable)
For maxing-out human detectable motion fluidity (eliminate stutters, eliminate tearing)
-- For VSYNC ON, framerate=Hz
-- For VSYNC OFF, framerates _massively_ exceeding Hz
For minimum input lag.
-- For VSYNC ON (double buffering), framerate=Hz
-- For VSYNC OFF (or proper non-chained triple-buffered VSYNC ON), framerates _massively_ exceeding Hz
But that's not "required".
You can still benefit from a 120Hz monitor at any framerates.
Just is what's needed to "max-out" fluidity on a monitor, which isn't something one "needs" to do.Edited by mdrejhon - 9/9/13 at 5:48pm