Here's something interesting that can be used with GPUs dating back to Nvidia's 900 series and AMD 400 series. Nvidia's Null + Reflex vs AMD's Anti Lag + Boost.
TLDW:
Having the highest frame rate in a game increases system latency dramatically in GPU bound scenarios because the CPU is processing frames faster than the GPU can render them which cause the Render Queue to fill up and significantly increase system latency.
Nvidia and AMD came came out with NULL and Anti-Lag at a driver level but that helped decrease system latency only slightly as it's done only at the driver level.
Capping your framerate with a framerate limiter so that the game wouldn't be GPU bound decreased the system latency drastically compared to both NULL and Anti Lag. Previous tests shows 40% difference by using a framerate limiter instead of NULL/Anti Lag. The problem is this requires user tuning each game.
Nvidia and AMD now has new solutions to this problem at an in game level but goes about it in different ways.
Nvidia Reflex which acts a dynamic framerate limiter with no user tuning apart from turning it on. You won't notice much of a difference to the framerate. AMD Boost decreases the Render resolution of the game by up to 50% when it detects your mouse movement in order to increase your frame rate. It can double your framerate while running at half the resolution until the mouse movement stops and then it goes back to the original framerate and resolution. And yes, when you stop moving the mouse or the mouse movement is slow, AMD's solution stops working.
The result is that Nvidia's Reflex decreases system latency drastically while AMD's Boost decreases system latency slightly (but more than just having Anti-Lag enabled) while causing frame pacing issues and rendering at a lower resolution which causes blurring affects and sometimes game crashes. The reason being is that Nvidia's Reflex aims to clear the Render Queue before the next frame gets processed by dynamically adjusting the submission timing of rendering work to the GPU. Where as AMD's solution just increases the framerate but the problem is that... The game can still be GPU bound... Just at a higher framerate which still lowers latency, just not nearly as much.
So while Nvidia Reflex game might be running at 60fps vs AMD's game might be running at 120fps. Because Nvidia Reflex actually makes sure that the Render Queue is clear, you will have a much more responsive game even though it's running only at 60fps. Quite the interesting test!
As an example, in Overwatch (Lower is Better):
Nvidia Reflex: 50ms with Standard Deviation at 59ms to 41ms
AMD Boost: 68ms with Standard Deviation at 86ms to 49ms
Last edited by Jizz_Beard_thePirate - on 19 March 2021