Gtx 1080 lagging in Gta V

Aug 5, 2018
10
0
10
Okay so my rig is:

Intel I7 8700K
Gigabyte Gtx 1080 Gaming G1
16GB DDR4 RAM
Samsung 860 evo SSD
Windows 10 Pro 64 bit

I'm trying to run Gta V on the highest settings on 1440p resolution.

According to this source I should be getting above 90fps:
http://www.userbenchmark.com/PCGame/FPS-Estimates-Grand-Theft-Auto-V/3727/137575.347462.Max.1440p.0
Other internet sources suggest similar performance.

But when I play the game I feel intense fps drops in environments with a lot of vegetation.
In the city the fps is usually smooth, but in country roads/forests it drops down to and stays at 20-30 fps (unplayable).

In task manager, I can see that my CPU isn't even crossing 50% usage, but my GPU immediately spikes to 100% and stays there as long as the game is unpaused.
I can hear my GPU fans working hard as soon as I unminimize the game window.

This is unusual because my GPU should be able to handle this game on max settings even in 4K.

My Nvidia drivers are up to date and my computer scores highly on benchmarks.
 
Aug 5, 2018
10
0
10


I did run it on fullscreen mode. I always do.
 
Aug 5, 2018
10
0
10


I'm definitely running the Nvidia drivers.
The default MS driver wouldn't even be able to launch this game...