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For various reasons DayZ is still my FPS of choice, sure development has been slow and it has it's fair share of problems but it's still fun and updated often enough to keep me coming back regularly. The biggest problem is that performance in large cities is just terrible. It is completely CPU bound and I'm talking 15-20 FPS being the best anyone can get regardless of CPU, GPU, graphics settings, launch options, core unparking, cfg tweaks, etc, again, completely CPU bound unless you're talking 5K+ for your resolution. I know, I tested it with DSR, my GPU is a GTX 780 BTW.

CPU wise I'm still running a 2600k but it's OCed to 4.2Ghz, sure I could probably take it to 4.6Ghz or something and help a little but it won't matter a lot as part of the problem is that the rendering is tied to the simulation speed that runs server side so until that is decoupled in a future update performance is sort of capped anyway. I monitored CPU/GPU/RAM/VRAM usage while playing this weekend @ 2560x1440 with all settings maxed except edge smoothing and post processing (because don't like the way they look) and here's what I found in four different common areas.

Large cities: CPU usage ~35% - GPU usage ~40-60% - FPS 15-20: limited by CPU
Rural towns: CPU usage ~30-35% - GPU usage ~30-40% - FPS 25-40: limited by CPU
Dense forests: CPU usage ~25-30% - GPU usage ~80-100% - FPS ~30-50: limited by GPU/detail settings
Open fields: CPU usage ~20-25% - GPU usage ~30-50% - FPS ~50-60: limited by vsync

Bonus info: RAM usage was ~3.5GB, VRAM was ~2.6GB in big cities and ~1.9GB most other areas, CPU usage was primarily in one thread (~90-100%) with a second helper thread doing a decent amount as well (~40-50%), the other two cores registered ~10% usage. Hyperthreading was on but 4/8 logical processors were essentially idle.

So the question is, and I'm not expecting miracles here (I have not delusions it will look "smooth" in these worst case scenarios), when frame-rates are that low would a 144hz screen be significantly better than a 60hz display? Knowing that G-Sync is going to show me the next frame as soon as it is ready it seems like being able to show it to me in 6.9ms instead of 16.7ms would be a pretty big deal, especially if the next frame is going to take another lengthy 67ms or whatever to arrive. TL;DR START HERE: Most of the reason I care about G-Sync is for it's impact on low frame rates so I didn't care too much about high refresh rates since I don't even want to start chasing that rabbit - BUT if a high refresh makes helps mitigate high frame times by ~10% or so then maybe I do care since that's more impact than I can expect from other factors (like overclocking my CPU further in this example)...

Thoughts?

Thoughts...........

"Large cities: CPU usage ~35% - GPU usage ~40-60% - FPS 15-20: limited by CPU"

Ya wow, that must be a horribly coded game. 15-20 fps and only ~35% cpu usage

Weird.

Oh yeah, it sucks, make no mistake, just barely multi-threaded and no way of knowing if I am capped by my own CPU or by the server, very ugly situation. Just trying to make the best of it. Luckily you can have a good experience without ever going to the big cities if you want. Also since it's not "twitchy" like other shooters and because everyone has to deal with the same problem it's not quite the deal breaker it sounds like if you enjoy the core of the game.

Both 144 Hz and G-Sync would be an improvement, but I wouldn't expect night/day improvement.

G-Sync's lower bound comes down to two things. First, refresh time. The higher the monitor's refresh rate, the low the refresh time, and that means that once the GPU sends out a new frame, it arrives at the user ASAP. This draw time is 16.7 ms for 60 Hz, 8.3 ms for 120 Hz, and 6.9 ms for 144 Hz. The second factor is the minimum refresh interval. TN pixels will fade to a neutral state if they don't get nudged back. G-Sync will do this maintenence when FPS is lower than 30 (FreeSync below 40 FPS, IIRC).

If you're below 30 FPS, you're losing a lot of the benefit of G-Sync because it's dropped into pixel maintenence mode. It should be slightly better than traditional V-sync thanks to higher refresh speeds, and it will still refresh to the newest frame as soon as possible, but there will still be a lot of redundant and old information being sent out because the game isn't generating new graphical information fast enough.

I presume you have checked out the toob?

https://www.youtube.com/watch?v=Vbx7UGKnYXo
https://www.youtube.com/watch?v=RDGVo3wY79Q

Yeah, first link is pretty much the standard set of tweaks any of the guides will tell you, honestly it doesn't help much over no tweaks at all unless your machine really sucks. It's much harder/impossible to solve the problems when the game/engine is the problem not your PC.

The second link is a bit too extreme lol, view distance is too important to do anything that drastic, no one could actually play the game like that, not sure how far into the video you watched before posting...

So another thought on this... When discussing multi-GPU and micro-stutter, it is possible that a 60Hz adaptive sync screen would be better at "leveling out" the frame delivery than a 144Hz one? I'm thinking that the perception of frame delivery on the 144Hz screen could look closer to what the frame time graph might look like in a problematic scenerio where the 60Hz can't actually show the "badness" as well. Does that make any sense?