as i mentioned i will buy new monitor in August, is that the reason tho?
Yes and no. Resolution has an impact on frame rates and depending on the amount of fps will depend if the cpu is capable of supplying pre-rendered frames the gpu is able to do. That's part of it. Other aspects of the cpu is it still needs to prioritise other game related tasks without being overwhelmed by the graphics card. Lower resolutions can see an increase in frame rates and also cpu load. Games like BF with so much going on + multiplayer, this alone is enough to saturate a cpu and adding frame pre-rendering to the mix can easily tip a cpu's usage levels quite high limiting resource efficiency.
Watch this video to understand what i mean about frame rates and cpu usage.
BF1's weight on cpus is similar to BF5 and other games too like Ghost Recon, Six Siege, Farcry, AC etc. Big open world games & multiplayer is a big job for a cpu and also not all games are optimised well and wont play smooth all the time.
There are different types of stutters. Micro stutters is more to do with frame syncing and another type of stutter is when a component is lagging behind. Frame rates do play a critical role in a cpu's performance but it's not entirely the only reason for stutters. Reasons can be vast and could be things like;
- Background applications zapping cpu resources. Applications like Discord where if possible use affinity to move the program to another core. Reason being is games still rely on the primary core, doesn't matter how well threaded they are. Threaded cpus help but If a cpu is struggling it could be helped by closing or moving user apps away from the primary core (#0) to reduce it's combined usage and avoid affecting the other cores.
- Drivers, software and condition of Windows. Driver booster programs are not a good idea, always keep to the manufacturer's drivers, ie motherboard, graphics card etc from their website. Certain software can be resource hogs or have other issues, investigating processes in task manager if system is under performing is a good start and doing a malware/virus scan. Upgrading Windows to a different version ie; going from Win 7/8.1 to 10 or continuing with an previous Windows install from a different computer can cause conflicts, a fresh install can work wonders under these circumstances.
- Temperature issues where the cpu or gpu throttles to slower speeds reducing instructions per clock slowing things down.
- Ram related, 16GB is enough most times but there are some games showing limits and excessive pagefile usage (Window's virtual memory). Windows consumes 2~3GB for itself, BF5 is pretty memory hungry and additional background apps adds up. Similar idea to cpu's usage and processes. Can get an idea of pagefile usage by looking at committed in task manager > memory, and deduct 16GB from the left value and that's how much pagefile is in use while playing a game. Committed combines both physical and virtual memory. Virtual memory resides on the drive Windows is install on, having pagefile get too large can impact performance. It is possible to customise pagefile size, there are tutorials about if you want to give it a try.
Diagnosing stutters can be difficult if it's software. Hardware can be pretty straight forward, commonly being there's either too much going on (need an upgrade) or there's throttling.
Going back to your monitor question, RTX2080 is capable of many fps in 1440p, so most likely you'll still have the same problem. Im not sure how many frames Ryzen 1600 is able to handle (In these games) at the same time doing other game tasks without running into some stutters. I thought perhaps Vsync capping fps to 75Hz would be enough, might have to go lower to 60fps using a fps limiter program like Afterburner or Nvidia Inspector or set the refresh rate to 60Hz and let Vsync cap fps. If you don't like input lag, try cap fps a couple frames below the refresh rate. It's an unorthodox way of doing things but the extra frames sort of act like a phantom buffer and with Vsync on there's little input lag if any at all, i used to do it this way. Having Vsync on helps sync frames to the monitor's refresh rate, timing frames to reduce micro stutters / frames clashing giving a jitter effect.
Use Msi Afterburner to monitor stats for cpu, gpu and ram in-game. Look at usages, temps and frequencies. For cpu usage stats there are fields such as cpu1 cpu2 usage etc that monitors all cores individually, can have these checked but there's another field called cpu usage (no number) that shows combined usage, have this checked as well.
If you're considering a new monitor, look for one with either Gsync or Freesync. Freesync now works with Nvidia cards if monitor price is an issue but it only works with Displayport cable. If Freesync interests you search confirmed monitors because not all have been tested. Variable sync helps smooth out frame dips and variations. It wont completely solve stutters but every monitor nowadays has either of the two sync technologies and think you'll like it.