fglrx multi-monitor configuration?

[bridgman]

AFAIK most of the boards that were shipped in the last several years were configured for multifunction support by default. I suspect the drivers simply ignore the second adapter and use both display controllers on the first adapter.

[Porter]

Any idea on how I should proceed, bridgman?

Based on the log I posted, should I try creating independent Monitor sections in xorg.conf, or is that a fool's errand?

Thanks!

[bridgman]

Not sure yet. There probably is a valid technical issue behind what the ASRock support guys are saying but right now I don't have any idea what it is. I'll try to hook up with the BIOS team next week and see if they have any ideas.

Since they are talking about primary and secondary adapter (but there's only one GPU) one possibility is something related to multifunction mode but I didn't think that normally limited which video outputs you could use. The only other possibility that comes to mind is some kind of video switching hardware (multiplexing a video output from the chip) which isn't initialized at power-up and which needs special code to operate.

You can dump out the BIOS image with the rhd_dump utility included in the radeonhd source tree. I think you have to build it yourself though. There's also a BIOS disassembler tool that formats and displays the contents of the AtomBIOS command and data tables; you can check Matthias's blog (emmes.livejournal.com) for more info.

[Porter]

Excellent, thanks for the info!

[Porter]

Oh, quick question... do you have to actually be running the radeonhd driver to use the rhd_dump (conntest) utility, or can it be compiled separately and run correctly on a system running the fglrx or radeon driver?

I'd like to avoid hosing the system (or inadvertently corrupting the VBIOS) if I can avoid it. I'll shoot a question to Matthias as well.

[bridgman]

I don't think you need to be running radeonhd; in fact it's best if you aren't running X at all AFAIK.

[Porter]

I solved it.


Turns out it was a "perfect storm" of weird behavior between my monitor and the integrated HD3200.

The Westinghouse 37" monitor turns out to have bad EDID data, but only on the DVI connection. Through DVI it reports the same EDID as through the VGA connector, i.e. analog rather than digital. Through HDMI it reports itself correctly (digital). Apparently this was an error in production, they literally just flashed the wrong EDID data to the wrong input section somehow.

Since the display reports itself as analog via EDID, the GPU shuts off the digital side of the DVI port and outputs analog only via DVI, I guess to save power or reduce EMI or something. Since the display's DVI input is DVI-D only, it displays nothing when this happens.

Behavior when attached to the HDMI input on the display from the DVI port on the PC (using an adapter) is flawless. It reports itself correctly, displays a great image at all times, etc.

So now I'm beating my head against the wall with the display manufacturer trying to explain to their (entirely non-technical) tech support staff what the problem is with the display. Somebody shoot me.