Hi everyone! The backstory: I recently upgraded to a 120 Hz G-Sync monitor and set it up following the advice found in Blur Busters' G-Sync 101 guide. Their tests state that one should avoid hitting the monitor's maximum refresh rate, as this will cause V-Sync levels of input lag. In order to achieve this, in-game limiters are generally preferrable, since they (mostly) cause 0 additional input lag. However, in-game limiters are not always available, and not always very precise or reliable (they often allow higher fps variances, spikes if you will, which might reach the monitor max after all). In order to take care of these cases, they recommend using an external frame limiter. This is where RTSS comes into play as a backup/alternative, because compared to other external methods of limiting fps, it apparently causes the least amount of input lag. They state one should set it to a minimum of 2 (recommended 3) fps below the monitor's maximum refresh rate, which I have. For most games this seems to work great, however I've come across situations now where things aren't working as expected. I've only had the new monitor (and gpu) for about 2 weeks now (tried a dozen games or so at most), so there might be many more occurances of this, yet to be found. TL;DR The problem: In some games (the ones I've found so far are CoD-BO4 and Sea of Thieves), if at any point RTSS's frame limiter kicks in, it causes negative mouse acceleration. My observations: it doesn't matter if you have G-Sync enabled or disabled it doesn't matter if you have NVIDIA control panel V-Sync enabled or disabled (read the Blur Busters guide if you don't understand why this is needed) it doesn't matter if the RTSS frame limiter is set below or above the monitor's maximum refresh rate, only that it becomes active it does matter what your mouse polling rate is set to, at 125 Hz it's barely noticeable, at 1000 Hz it's atrocious and unplayable if you require any kind of precision (I've tried several mice to be sure) Please note: I'm not by any means disregarding the possibility that I've made a mistake somewhere and something entirely different is causing the issue. While I am tech savvy, there is always someting one doesn't know, and perhaps I'm drawing the wrong conclusion here. However, right now it seems that the problem lies with RTSS. I am also aware that there are workarounds available here, the ones I can think of are: lowering mouse polling rate as far as possible (only reduces the severity of the problem and creates different disadvantages instead) turning off RTSS frame limiter for the affected games, manually or by using profiles (results in severe input lag in certain scenarios) using a different external frame limiter, such as NVIDIA Inspector (results in higher input lag than necessary) lowering in-game frame limiters (where available) to the point where they 100% won't reach the monitor's max (Black Ops 4's limiter seems especially weird here, I can lower it all the way to 112 fps and the game will still run at 120 most of the time, but once I reach a limit of 111 fps it drops down to 105-107 and doesn't seem to even reach 110), this is probably the best option right now, but lowering these too far (as would be required in BO4) results in higher frame times as well, which again you don't want Conclusion: It seems like a bug to me (at least I really hope it is, a fix would be wonderful). Maybe it isn't and can't be avoided, but I wasn't able to find anything using Google or the forum search, so here we are. I'm curious what you guys can say about it.