Full screen = greater than 50% FPS drop

[LightDefiant]

Recently (about the time of the last MacOS update) I noticed a inability to run my game full screen without major FPS drops. I have attempted a full reinstall but the issue persits.

I am currently playing in a window, which is acceptable but was wondering if there was something I could adjust to all me to go back to full screen playing without having to deal with 14 FPS in an empty world. UPS is holding at a stead 60.

Any help with possible ideas on the problem, or a solution would be greatly appreciated.

Thanks for taking the time,
LightDefiant

Screenshots and System Stats as follows:

Full Screen

Screen Shot 2018-04-10 at 2.27.20 PM.png (6.14 MiB) Viewed 1245 times

Windowed (apologies for the overlapping stats, just happens when I switch to windowed mode)

Screen Shot 2018-04-10 at 2.27.59 PM.png (3.41 MiB) Viewed 1245 times

Model Name: iMac
Model Identifier: iMac14,2
Processor Name: Intel Core i5
Processor Speed: 3.2 GHz
Number of Processors: 1
Total Number of Cores: 4
L2 Cache (per Core): 256 KB
L3 Cache: 6 MB
Memory: 16 GB
Boot ROM Version: IM142.0129.B00
SMC Version (system): 2.15f7

Chipset Model: NVIDIA GeForce GT 755M
Type: GPU
Bus: PCIe
PCIe Lane Width: x16
VRAM (Dynamic, Max): 1024 MB
Vendor: NVIDIA (0x10de)
Device ID: 0x0fea
Revision ID: 0x00a2
ROM Revision: 3782

[The-Killer]

Same for me on windows, seems to be related to Atlas Texture Size Option.

Default was "Largest Possible". Changing it to even 8192 made it a lot smoother for me, 4096 made it smooth as butter. In early betas of v16 it was like that for me too, but it was smooth towards the last few beta versions so dont know what changed upon release.

My Specs:
GPU: GeForce GTX 970
CPU: Intel(R) Core(TM) i7-7820X CPU @ 3.60GHz
Memory: 16 GB RAM (15.71 GB RAM usable)
Current resolution: 2560 x 1440, 60Hz
Operating system: Microsoft Windows 10 Pro