Questions
Q1
Why my H61/H67 system has unkown device when using PCI-E VGA card?

Due to PCI-E VGA card has HDMI output, so the on-board HDMI device will need to install the seperate driver for system to detect it properly.

Please download following driver for Windows XP OS to fix the HDMI audio device problem.
https://www.biostar.com.tw/files/faq/intel_6x_hdmi_xp.rar