Windows 7: What ext video card takes SPDIF audio from ext sound card?

Presently I have to use onboard sound card to have audio through HDMI output from video card. The external sound card installed is Xonar DG and it comes with SPDIF output header to be interfaced with video card. But I do not see no such header on the video card. I wonder what video card has such an interface header.

I don't think they meant for it to be plugged into any video card...

I wonder then what they mean.

That was only needed with Nvidia cards from the 8xxx series up to the GT/GTX 2xx series ( I believe starting with the GT/GTX 4xx series it was integrated on the card), as they didn't have native audio on the for HDMI sound. This is what you are referring too,

Guide: 8800GT/9800GT/9800GTX Sound over HDMI (Now including Creative cards)

The card you have has its own audio chip on it (Realtek) with no need for the SPDIF connection, and all ATI/AMD cards from the HD 2xxx series and up have been the same. The driver for it is included with the video driver in the Catalyst suite. Once installed it is just a matter of setting the AMD HDMI audio as the default playback device in the Windows audio settings.