alt Hacker NewsIt looks like consoles and PCs have settled on somewhat different gaming configurations. Consoles usually try to target a fixed output frame rate, while the resolution is often dynamic. On PCs, by contrast, the resolution stays static, while the frame rate and frame-time pacing are dynamic. How does this fit into the latency discussion?
Especially in competitive gaming, I often see people targeting frame rates way beyond their display’s refresh rate. I’m not sure whether this actually provides a real benefit or whether they’re chasing a placebo effect.
Am I out of touch, or is it the children with colored LEDs on their DRAM sticks who are wrong?
Replies
> I often see people targeting frame rates way beyond their display’s refresh rate. I’m not sure whether this actually provides a real benefit or whether they’re chasing a placebo effect.
If they are chasing a placebo effect, it's a really powerful one, since all the actual competitive people are often willing to sacrifice all detail and quite a lot of resolution to get those stupid high frame rates.
I can see the difference too, but the diminishing returns usually make it not worth it, since I prefer the eye candy better details and higher resolutions give me.
Also, some games can adjust the resolutions on the fly to keep a consistent frame rate. It's only become a feature on modern games, but I believe that's mostly a historical accident. PC games could often run on much worse hardware than they were actually designed for (with minimum requirements often being absolute minimums, and not 'this is what we developed for'), so people played them on low frame rates, so that kind of jank was often more culturally accepted on PC, and if you didn't want that experience, you could always upgrade. While on console, there was no upgrade path, and games were optimised for that one config, and thus never allowed to drop too far into the red (and dropping resolution is often a better option in those cases).
Framerates beyond your display's refresh rate are not completely pointless, though a bit wasteful: they do mean that each frame as it is displayed shows a more up-to-date representation of the game state than if your framerate is matched to your refresh rate. In principle you don't need to render the excess frames: ideally your frame time is predictable enough you can kick off the render just before the display refresh, but the penalty is that if you miss the deadline you get some pretty jarring jankiness.
> Especially in competitive gaming, I often see people targeting frame rates way beyond their display’s refresh rate. I’m not sure whether this actually provides a real benefit or whether they’re chasing a placebo effect.
In video games you essentially have one giant loop that runs every frame (today it's more than that, but at its core it's still that). Producing frames faster than the display’s refresh rate can still reduce input latency because the next display refresh is more likely to use a recently generated frame. It does not necessarily mean the game receives more input events, but it can process and reflect those inputs sooner.
Not placebo, but diminishing returns become significant, and the benefit depends on frame queues, VSync, VRR, whether the game is CPU- or GPU-bound, and how its input and simulation loops are designed.
Many PC games have dynamic resolution, too. The reason consoles target 60fps is because that’s the frame rate you get with most TVs and everyone playing the game has the same hardware (or couple variants).
> Especially in competitive gaming, I often see people targeting frame rates way beyond their display’s refresh rate. I’m not sure whether this actually provides a real benefit or whether they’re chasing a placebo effect.
A newly rendered frame can cut-in during scan out. This shows up as tearing artifacts where the frame is changed while being sent to the display, but it allows fresher pixels to hit the screen below that tearing line. So each frame on the monitor can be a mix of multiple rendered frames.
It’s not as good as having variable refresh rate display with high refresh rate, but it does reduce latency.
For less action based games it’s common to turn vsync on and pace the frames to the refresh rate to eliminate this tearing.
Running above the display refresh rate is only decent when you are wayyyy above it, at least double. If you have a 120hz display and run something variable around 150fps, its much worse. But 500fps does help, you're basically seeing more recent frames as it scans the screen.
> I often see people targeting frame rates way beyond their display’s refresh rate
Could this be to reduce input lag?
As someone who is in the rendering space for work. Having a higher framerate does help, but in a weird way. Basically the start of the frame rendering is what mostly dictates where objects are rendered. By getting a higher framerate the position of objects that you see in game are much closer to their "real" position. So it's less about seeing more frames at that point and more about seeing the most up to date information possible. Technically it could be possible to render the frame in sync with the framerate and just offset the rendering so it finishes right before it's pushed to the screen, but if you're slightly wrong you'll get really bad stuttering and the execution time of gpus and the cpu submitting the work isn't really deterministic.