Question / Help OBS is forcing games to 24fps while simply running (no stream/record)

[Kuram]

It is a similar issue of the problem explained in the following link, but nothing in that thread worked for me (except I did not try reducing my monitor's refresh rate to 60hz as that is not an acceptable solution for me so I don't care if it works or not):
https://obsproject.com/forum/threads/obs-is-causing-games-to-take-a-major-fps-hit.46991/

As for hardware, I run a 1080ti, on a 1440p 144hz monitor with g-sync, 4790k processor OC'd to 4.6 if I remember. In my experience g-sync on or off made no difference except for only one game (Hollow Knight). Typically I can fix the issue temporarily by cycling the game between exclusive fullscreen and windowed, but this solution doesn't always work (always does in PUBG, about half the time in Divinity: Original sin 2, and never in Cuphead).

I used to get the same problem without OBS, but I've since fixed that by disabling windows fast boot.

Log file attached. The issue does not require streaming or recording to take place. The problem happens as soon as OBS is launched. It does not matter if OBS is launched before the game or after. It doesn't matter if it's game-capture or window-capture. Doesn't matter if it's x264 or NVENC. Doesn't happen with Shadowplay (if that matters).

Issue never happened on my previous setup which was a 970 with a 1080p 144hz monitor (no g-sync).

If you need more information, let me know.

edit: two other peculiarities I forgot to mention. If the game is windowed and it loses focus, the FPS goes back up to usual numbers, and it does not matter if the OBS preview is activated or not.

 

[Fenrir]

First, OBS cannot directly affect your game. It's just not possible, it doesn't attach to anything on your system that can direct affect your FPS in the game like that.

Second:

init_hook_info: user is forcing shared memory (compatibility mode)

Turn multi-adapter compatibility off in Game Capture properties. You should have never turned this on, as this option has a SIGNIFICANT performance cost. This may explain all the issues you're having.

However, Windows 10 systems that have monitors that have two different refresh rates have all sorts of issues when it comes to operating with OBS on. See: https://obsproject.com/mantis/view.php?id=676

If you are not willing to perform any "unacceptable solutions" just to test and confirm what is actually going on, there is probably not much we can do to help. This kind of thing is completely outside our control.

 

[Kuram]

>First, OBS cannot directly affect your game. It's just not possible, it doesn't attach to anything on your system that can direct affect your FPS in the game like that.

Well that's completely untrue, as soon as I turn OBS off my FPS returns to normal. Turning it back on again reduces my FPS.

Changing the refresh rate seems to work, but for now I don't know if it's temporary or not. Certainly not ideal.

 

[Fenrir]

It's not untrue, it's fact. OBS cannot directly impact your game.

It can, however, cause your PC to become overloaded because it can't handle the stress of running a game and OBS at the same time.

It can also use task your PC for things that most applications don't normally touch (such as Windows capture methods) that can cause bugs in Windows itself to present itself. The monitors with two different refresh rates causing issues is a Windows 10 bug, and there's not a whole lot we can do about it. Other capture programs have the exact same problem, so it's not specific to OBS.

Correlation does not equal causation. There's a lot of moving parts when OBS is open, and it's easy to blame the program when you don't understand what's going on behind the scenes.