For the longest time I had questions in my mind regarding v-sync when used with a Freesync display. So I will list my questions straight on:
I have a 144hz FreeSync display with a range of "FreeSync Range - 48 to 144 Hz reported by display" as reported by Adrenalin software. If I enable v-sync in a scenario where the game is running within the FreeSync range at all times (never going below 48 fps and never going above 144 fps), does v-sync have any effect? Do they still work together at the same time or does FreeSync simply override v-sync leaving it pointless?
Using the AMD FSR 3 swapchain, VSync enabled and disabled modes are the main differentiators in terms of frame pacing. When VSync is enabled, pacing relies on the expected refresh rate of the monitor and will present game frames as quickly as makes sense – as ultimately, the monitor will swap to the queued frame images in a consistent way behind the scenes. A game using AMD FSR 3 in this configuration will show a “zig-zag” pattern on frame time / present-to-present timing graphs. This is expected.
There are more accurate ways to examine frames through the display pipeline to a monitor than present-present. The gameplay experience in this mode is recommended due to its more consistent timing – when combined with a game-side frame time limiter set to ½ refresh rate, it is a high-quality gaming experience.
Now, what confuses me here is that on a FreeSync monitor, turning v-sync on does not limit the framerate as long as I am within FreeSync range. It only limits framerate to 144 fps when framerate exceeds FreeSync range as well as when framerate drops below FreeSync range. I guess this is directly connected to my first question. Does v-sync actually work while framerate is within FreeSync range?
This is causing confusion to me, because in Avatar - Frontiers of Pandora, for example, my game hits stable 70 fps but because that's within the FreeSync range, fps still fluctuates a bit. So in this case, to get the optimal frame generation quality, what exactly should I do? Simply turn on v-sync or limit the framerate to 1/2 the refresh rate as specified on the AMD website while also keeping v-sync on. Or does v-sync have no effect at this point since I am within FreeSync range?
I guess answering the first question also answers the second question at this point. So if you could clear this confusion I would really appreciate it. I did a Google search already but everyone is saying something different and it confused me even more.
Thanks a lot for all the answers in advance and have a great day!
