Clarifying Basic Motherboard Sound Output

[Caveman]

Looking to shore up my understanding of what's going on with MoBo sound. Please correct any misunderstandings:

1) All outputs are active at the same time... Hook them all up and they should all work simultaneously... 1/8" jack on case front panel headphones, 1/8" jack on the mobo outputting to a set of speakers... SPDIF jack on MoBo going to stereo receiver... All can produce same sound at some time, yes?

2) What about HDMI or Display port of a GTX 970 going to a stero Rx? Do these cables carry mobo sound as well as video? How does the MoBo sound port over to the video card HDMI port? Is it through the PCI E bus?

 

[WildW]

This response is for Windows. Other operating systems might do things in a more sane way...

1) Generally, no . . . Windows (from Vista onwards) treats most sound outputs (even on the same sound-card, integrated or not) as separate devices. You can do some clever things with some programs such as selecting different sound output devices per program if each program in question has an option for it. This is useful for, say, having most sound come from your PC speakers but setting your video playback software to output sound to the HDMI port your TV connects to. . . my head gets confused if the TV sound doesn't come from the TV.

However, generally you have a default sound device that all programs will output to, and you can't usually output the same thing to, say, both line-out and SPDIF at the same time. A look in Control Panel->Hardware and Sound->Manage Audio Devices will show you the different sound output devices in your computer

The exception to this can be the line-out and headphone jacks. On my machine the headphone jack mutes the line-out when connected, but I see in the Realtek sound options I can turn this off and drive both at once as they seem to be the same output device...or make them separate devices.

2) HDMI/etc on video cards come up as separate audio devices again. You can select any one of them for sound output but again, you can't choose to output the same things to multiple devices.

 

[Caveman]

Thanks for the reply. Interesting...

on #2, I guess the sound comes through the MoBo through the PCI-E interface?

Sounds like I may be able to port sound via HDMI to a stereo Rx and then output to headphones and speakers driven by the Rx. Or... port HDMI sound to the Rx and still be able to use the front jack for some headphones...