ASRock Z77 Pro4 manual Serial port Header

Serial port Header	This COM1 header supports a
(9-pin COM1)	serial port module.
(see p.13, No. 28)

HDMI_SPDIF Header	HDMI_SPDIF header, providing
(2-pin HDMI_SPDIF1)	SPDIF audio output to HDMI
(see p.13, No. 29)	VGA card, allows the system to
	connect HDMI Digital TV/
	projector/LCD devices. Please
	connect the HDMI_SPDIF
	connector of HDMI VGA card to
	this header.

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