Dual Output on Mobility Radeon HD 3470

[Richard Palmer]

Dear Michel,

> On Mon, 2010-01-04 at 17:58 +0000, Richard Palmer wrote: 
> > 
> > 	I have two Dell 20" monitors connected to a Mobility Radeon
> > 	HD 3470 card using DisplayPort to DVI adaptor cables. I can happy
> > 	use either monitor, but not both together. xrandr lets me
> > 	switch between them, showing different parts of the virtual desktop
> > 	(with compiz enabled), but I haven't found any way to get it to
> > 	show both.
> 
> IME compiz doesn't handle dynamic RandR configuration changes well. Try
> without compiz or manually updating the compiz output configuration to
> match the RandR configuration.

Sorry, I should have said that this starts at login; both monitors
work in text mode (showing cloned output) but when gdm starts one
monitor goes into power saving mode. I start compiz after I've logged in,
so don't think it can be this causing the problem?. If I switch back to
the console from X both monitors are enabled again for text, switching back
to X turns one of them off again.

Any thoughts ?. It's rather frustrating as it all seems to be working in
parts, which makes me think it's just a question of configuration error
on my part rather than missing functionality from the driver.

thanks,

Richard


-- 
Richard Palmer			| Centre for E-Research &
Systems Manager			| Centre for Computing in the Humanities
richard.d.palmer at kcl.ac.uk	| King's College London
Tel: 0207 848 1973