Yea, I have to boost it manually too. It'll likely be eventually updated as Eternal Crusade is a bit of a kinda well-known game.

I7-4790k @4.0 Ghz
8 gigs Kingston Hyper X @ 1600
Asus GTS 970 OC
100g SSD
25 ms

I am capped at 80 fps with shadow play running. Random screen freeze for a second, due to server.

DO you think it could be a lag issue possibly, whats your (ms) ? Your system is stronger than mine. It cant be a hardware issue.

The problem is not only the gpu, the game just is poorly optimised. Fps ranging from 25 to 90, constant random freezes, stuttering despite g-sync is neither good nor smooth performance.
What youre experiencing is odd though.

I have a similar system (980 GTX , 16 gb ram, i5-4670k OC'd to 4.0) and I get incredibly terrible FPS in this game . I get 15-35 fps on the smaller maps, and an unplayable 8-15 fps on the 30 v 30 siege map. I've tried turning all the settings down and disabling everything, doing the INI tweaks, updating to the new drivers, and lowering the resolution and playing in a 1200 x 800 window. I'm pretty much at a loss of what to do, but glad to see that i'm not the only one.

Could this be a game where the code works better for AMD cpus for once?
Nah, perhaps not but I use a GTX 960, 16 bg RAM, AMD FX-8370 none-oc so ticks at a leisurely 4 GHz.
Vsync does give me microstudder so that is off, but everything else is on Ultra. Frames capped at 60.
I play it at 1600x1200 resolution too (you have to fiddle with the settings a bit to get resolutions beyond the ones in the scroll list though, super annoying).

All I can think is that it might be due to what version of Windows you are using? I'm using 10, and it works fine for me.

I have Geforce 960GTX 2G and it runs stable around 60-35 depending on current situations.
Grafix settings on high and only option "on" is the distortion effect.
My cpu is Intel i7 4970 3,6 Ghz