OBS recording and Win 10 DVR

[Misfortunes]

Sorry if I'm in the totally wrong section for this question, but can anyone explain why the built in Win10 Game Bar recorder can record a window or game's audio only? I'm currently weighing whether to get the control and ability to stream that I can get with OBS, or just sticking to Win10 Game Bar recording because it can record a game (or zoom lecture really) without all other desktop sounds being recorded? I'm sort of looking for a break down on what powers the recording for Win10 GB. For context if it matters, I run an i7-8700K and an Nvidia RTX 2070, which I assume the gpu is being used for hwencode, but otherwise performance has no matters to me.

Thanks

 

[Misfortunes]

How exactly would I go about doing that, and where would I find those settings in OBS? What sort of device do I need to capture audio from the kernel?

 

[Misfortunes]

Oh, I understand how that works, and I've used it before.

I was asking more about how does Win10 DVR work. Thank you anyways!