OBS Studio FPS drops

[Timeless88]

Hello All,

 

i7-6700k (currently no OC)

GTX 1070 8GB

32MB of RAM

 

I do a bit of streaming on Twitch and I recently upped my stream FPS from 30 to 60.  What I noticed when I did this is that most of the time while I am actually playing games my FPS in OBS Studio is fluctuating wildly, usually between 30-45 FPS.  Sparing you all the boring details, I finally narrowed down the issue to my graphics card.  Specifically, whenever my GPU usage goes over 90%, my FPS starts to decline.  I normally game at 1440p 144Hz/144fps with low-medium graphical settings, and normally play Overwatch/Darwin Project/Fortnite.  Basically, I'm trying to figure out why even when my GPU is not maxed out do I start to get less FPS in OBS and if I can fix it in some way.  If that is enough for you to give me any useful information or make suggestions then don't worry about the below part.  Below you will find some specific scenarios I tested that reveal some strange behavior.

 

I have tested this with my graphical settings at 1080p and 1440p, with my StreamElements overlay both on and off.  Even having a static overlay dramatically lowers the FPS I get even though it doesn't seem to change my GPU usage that much.  For instance; gaming at 1440p 144Hz with medium settings and overlay turned on my FPS averages about 35.  However, if I turn the overlay off (with the exception of my web cam) I can be pushing my GPU regularly up to 98-99% usage and still only get FPS drops down to 57-58.  This FPS drop is basically exactly the same no matter how many elements I have in my overlay (I tested with a single webcam border, still dropped my FPS down).  Since StreamElements hosts your overlays via a web page, I tried using local graphics and still got the same declines in FPS, though slightly less.

 

I can accept that my system may simply not be able to handle gaming at 1440p 144fps at the same time as streaming at 720p 60fps, if thats the case.  And indeed I have verified that if I lower my gaming resolution to 1080p, I can stream with no FPS throttling even at full medium settings.  But this is also because at these settings, my GPU usage is maxing out at about 93% and averaging more in the 70-80% range.  My real concern beyond simply "Am I pushing my system too hard?" is "Why does my FPS throttling increase due to overlay graphics that don't seem to affect my GPU usage (or very slightly affect)?"

 

As I said before, any information, insight, and/or suggestions will be greatly appreciated.  Thanks in advance!