HDMI output over DVI to HDMI bundled adapter (Radeon HD 3870)

[Rafał Miłecki]

2011/11/6 Maciek Sujkowski <maciej.sujkowski at gmail.com>:
> Hello
>
> Does the radeon driver support HDMI "emulation" over the bundled DVI
> to HDMI adapter similar way as the fglrx/catalyst driver does?

There is no emulation, both DVI and HDMI use the same signal: TMDS.
ATI cards can add audio signal to DVI, so that's just like HDMI port.
You may want to read
http://en.wikipedia.org/wiki/Digital_Visual_Interface#DVI_and_HDMI_compatibility


> I've been trying to get HDMI output on my plasma TV (LG 42PQ1000) via
> radeon driver and each time there is "Invalid Format" message on the
> screen and there is no HDMI audio as well despite the audio output is
> set to HDMI.

What kernel are you using? Please, provide also output of:
dmesg | grep audio

Older kernels were enabling audio support by default. This support is
implemented from RE efforts only, so it is not perfect. Enabling audio
can sometimes break whole signal (not even video available, or
corruptions in more optimistic case).
If you're using some older kernel (with audio enabled by default), you
can try booting with radeon.audio=0

-- 
Rafał