Sudden Fps drop to 1fps.

[Nautinto]

So I just had this funny fps drop to 1! when i entered to ArcJet engine core cell.
and i was turning horizontally around and on some directions it was staple 60fps and on other parts 15-1fps.
I quess it was because my long gaming session... (shhyyy) 9hours.
Got one GTX 960 2Gt.
So when i entered the room and having such enormous lag I did little research and these are what i found.
GPU usage 100%, Memory clock speed 7200 MHz, Memory usage 2033Mt, Vram usage 6%,( 3D usage 100% from task manager).
From GPU system information: Reserved video memory 2Gt GDDR 5, Shared system memory 8Gt
From taskmanager memory usage 25%.
Also got i5-4690K 3,5Ghz CPU.

Let's see if problem is fixed after computer restart. (couln't find any valid information with quick search so made this one)

[EmilB]

i guess is gpu fault and ram 8 gb to low.

[r.linder]

For whatever reason, your GTX 960 is being pushed to its processing limit. Lower or turn off godrays, lower shadow quality and distance, and run the display at 1080p to maximize performance on that GPU.

[Nautinto]

well had another 2x 5 hour sessions and works fine. needed to just restart game and/or computer. and works fine.
What i'am interested for is max load? of what? that caused this problem? cause i got that 8gb extra system ram memory unuset. (for gpu?) so why it only used up the GPU base ram? "not a professional virtual stuff master" so I got no idea what so ever? was there some ingame ram limit or something? there is always that one mod for "better performance" or something. not using it.

[r.linder]

When a component is consistently being pushed to maximum load, it's being pushed to its limits. In the case of a graphics card, it's likely either a game's settings being too high, the screen resolution is too high for that model, or both. The GTX 960 is absolutely ancient at this point so it will struggle with a lot of effects, especially godrays.

There are exceptions, though, as in rare cases of software issues with the graphics driver, anything can push two 1080 Ti cards in SLI to max load and make them underperform. I doubt that's the case with your GTX 960, because that model is outdated, and wasn't great to begin with.