One thing about that kind of stutter is that it is really easy to see any game do that. If you unlock FPS in many modern AAA games that use tons of threads and let the CPU get thrashed you can see worse frametimes on average, like greater stutter, than if you let the game cap at 70 or 80 fps or something.
We noticed this pretty handidly when testing ultra hi fps in battlefield 5. The frametime graph when you let the CPU get saturated completely in that game goes to shit with a much worse subjective experience then just capping it and letting the CPU breathe.
That must only be in some games or with some API's though? Or maybe only in games that can effectively max all CPU threads.
CS:GO is heavily CPU limited for me but I don't seem to experience any frametime issues when running at 250+ fps.
If it's a case of the CPU getting hammered maybe it could be fixed with updates to the Windows scheduler or by limiting core usage. Specter/Meltdown fixes might also have a larger impact since they really hurt performance when it comes to context switching IIRC.
In BFV, every frame, it has to do physics sim and update positions of 63 other players. I have to cap my fps at 120 fps in BFV too, otherwise my CPU can't keep up and I get horrible spikes when there's an explosion. You can see this really well on the PerfOverlay graph (a diagnostics tool every released game should have :) )
While the aforementioned causes here could certainly be the case in many instances, I'll add that in my personal observations over the years (subjective, not objective, mind you; no in-depth testing), I've also noted that some engines appear to not handle variable frametime targets very well, and prefer sustained and/or even interval framerates (30, 60, 120), regardless of CPU capability, sync configuration, physics, tick rate, etc.
For instance, I was recently playing The Witness, and even though my CPU and GPU weren't even close to being saturated (8700k and 1080 Ti @1440p), and I had a 141 FPS RTSS limit (with G-SYNC @144Hz), I was getting recurring stutter. It wasn't until I limited the FPS to 120 that the stutter disappeared.
This issue probably depends on the given engine, regardless of system capabilities in certain instances, and RDR2 does not seem to like variable framerate (currently), period.
