Dual monitor lag issue

[Mr_Shepherd]

Hey guys

Has any solution been found to the "known" lagging issue when running OBS on 2nd monitor?

Main monitor is 165hz, secondary monitor is 60hz. When the OBS window is displayed on secondary monitor while gaming on primary, the recording is extremely laggy. If I drag the obs window over to the main monitor the lag issue immediately goes away.

Apparently this is a known issue? I would prefer to have obs window displayed on secondary monitor.

 

[FerretBomb]

It's a long-standing bug in Windows. The fix is to update to at least Win10 2004, preferably 20H2, where it was addressed (but not fully fixed, just mostly).
You can also run all of your monitors at the same refresh rate to fix it. Some have reported that right-clicking the Preview window and Disabling Preview also can fix it, as another workaround.

 

[Mr_Shepherd]

Would running the secondary monitor with a separate (second) Gpu solve the issue?

 

[FerretBomb]

Would running the secondary monitor with a separate (second) Gpu solve the issue?

(edit) No, it would not. I just realized in the course of typing up the explanation below, the bug is based in the Windows desktop compositor process. It would still have to deal with the same multiple refresh rates even spread over two GPUs.

---(Disregard below, I left it because I didn't want to delete after explaining the reasons why 2 GPUs is a bad thing for OBS)---
It could be worth a try, but would definitely cause its own problems with OBS.

Having a second GPU installed tends to split the PCIe lanes available to the primary, going from x16 to x8, which can/will affect your possible end-to-end frame-timing, leading to potential skipped frames due to render delays. If everything can't get to the GPU, be color converted, scaled, any filters applied, composited, and sent to the encoder with a certain time-margin, the encoder will just skip the frame. For 60fps video, all that has to happen reliably in under 16.7ms.
If you're using a lot of browser sources and update-heavy sources, that x16 bandwidth is essential.

You might be able to (depending on your motherboard) force x16/x1 mode, but I'm not sure if OBS running on the second (realized... here) GPU would be picked up and accelerated properly by the Windows desktop compositor.

 

[junerg]

I think i have the same issue, however i'm using 2 monitors that run at the same refresh rate normally. both are 60hz.
But when i have obs open on my second monitor whilst recording my gameplay is lags the preview (not the recording) just the small preview on obs