Bug 21604

Summary: r630: Second screen doesn't get signal in dual head mode
Product: xorg Reporter: Mikko Virkkilä <mvirkkil>
Component: Driver/RadeonAssignee: xf86-video-ati maintainers <xorg-driver-ati>
Status: RESOLVED FIXED QA Contact: Xorg Project Team <xorg-team>
Severity: normal    
Priority: medium    
Version: git   
Hardware: x86 (IA32)   
OS: Linux (All)   
Whiteboard:
i915 platform: i915 features:
Attachments:
Description Flags
Xorg log
none
xrandr output none

Description Mikko Virkkilä 2009-05-06 14:41:45 UTC
Created attachment 25572 [details]
Xorg log

Card: Sapphire HD 2600 Pro AGP

xorg.conf contains the following options:
	Option	"BusType" "PCIE"
	Option "ExaNoDownloadFromScreen" "True"

It has three physical connectors: DVI, VGA and S-Video. 

I have the first screen connected using DVI and the second screen connected using VGA. 

xorg recognizes both screens correctly and gets the right modes from the displays.

In "clone mode" (aka "mirror mode") both screens work and show the same image without issue.

When trying to use the screens in a dual head setup side by side, only one display gets a signal, the other display turns off. From a software point of view everything seems to work: the desktop correctly expands to both screens and  xrandr reports that both screens are in to correct modes. The only issue is that in reality, the second monitor has turned it self off.

By only enabling either one monitor, the single monitor works, and the one which is enabled later always fails (only primary display works?)

Playing with 'xset dpms force off' has no effect on the issue.

Playing with various modes and refresh rates using xrandr has no effect on the issue.

I also tried the latest radeon driver from git, it made no difference.
Comment 1 Mikko Virkkilä 2009-05-06 14:42:15 UTC
Created attachment 25573 [details]
xrandr output
Comment 2 Mikko Virkkilä 2009-05-06 14:45:56 UTC
tested git was xf86-video-ati master, commit
0c3541f7013c53fb8096ada63cc7b3577524aa4c
Comment 3 Mikko Virkkilä 2009-10-17 12:44:24 UTC
Works for me with 1.6.4. and doesn't require the "BusType" setting to be changed anymore. Performance is better as well (glx gears reports 900fps, up from 450fps).

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