Intel® EMGD supports only one type of SDVO-HDMI encoder, which is CH7315. SDVO-B cannot coexist with HDMI-B; SDVO-C cannot coexist with HDMI-C.
SDVO takes precedence over the HDMI port driver. If no SDVO encoder is available HDMI is automatically loaded by default (only in the GM45 Express chipset).
Internal HDMI is available only for the GM45 Express chipset. Only one HDMI port has audio at any one time. The first port in the port order has audio while the second port would have only display without audio.
Only one HDMI port has HDCP at any one time. The first port to receive a request for HDCP has HDCP enabled only in that port.