Asus M4a785-m and ntegrated ATI Radeon HD4200 output to 15" VGA Monitor and HDMI-TV

Luis Paulo luis.barbas at
Mon Oct 25 17:23:08 UTC 2010

On Mon, Oct 25, 2010 at 10:52, Tony Pursell <ajp at> wrote:
> On Mon, 2010-10-25 at 01:49 -0400, Mike McMullin wrote:
>>   I've got a bud who installed 9.04 on his new system (critical details in
>> subject line), and would like to be able to output to both his 15" monitor and
>> HDMI TV, the screen looks almost fine on the 15", but the full desktop is not
>> showing, and on the HDMI-TV you see the middle of the desktop with no upper or
>> lower bars, is there a way to fix this so that the desktop is proper size on
>> both the monitor and the TV?  (Driver file recommendations would be appreciated
>> as well.)
> The problem on your TV is due to what is called 'overscan' (Google it!).
> TV manufacturers deliberately make the picture bigger than the screen so
> you don’t seen the edges.  There is a standard for the position on the
> screen that can always be seen so that things like subtitles are always
> seen.
> I am not sure how you cope with this for your graphics. On my Acer Revo,
> with nVidia graphics, I can use the proprietary driver which gives a
> menu entry for my Panasonic Viera TV with an option for Overscan
> Correction.  AFAIK there is currently no proprietary driver for ATI
> Radeon (like I have on my desktop PC) and I don't know about any GUI for
> adjusting the parameters of Open Source drivers. Perhaps now I have
> identified the problem, someone else will be able to help.
> Tony

Just to say that I configured recently my 10.10 with a ATI Radeon 4800
to use an HDMI monitor.
I had to set the samsung monitor to PC mode (TV/PC mode). And:
* With xserver-xorg-video-radeon 1:6.13.1-1ubuntu5 driver it worked fine.
* With fglrx 2:8.780-0ubuntu2 driver, I had to set overscan (had black
borders all around)
Using fglrx-amdcccle (ATI Catalyst Control Center (Administrative)),
select Display Manager->your monitor->Adjustments Tab and set Scaling
Options to 0%, it was ok then  [1].

For the OP: Hope this may help. You may be doing two questions:
Setting for an HDMI monitor and Setting dual displays.

If I'm correct, I ask you to tell us if you can set your image on your
HDMI monitor, using only that monitor.

If so, then try both displays. As I remember, setting the same image
in 2 monitors with different resolutions may not be that out of the


[1] I also set my DPI settings on
System->Preferences->Appearance->Fonts Tab->Details ... Button on
resolution to 102dpi in my case.

dpi stands for dots per inch, and you can get that number from your
Xorg.0.log or by dividing your H resolution by your monitor horizontal
width in inchs.
The smoothing settings on the same tab may also improve your image.

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