Underscan from grub to gnome

[aspedisca]

Hello all,
I have been using gentoo for my laptop thus when I decided to employ an HTPC I decided to go with sabayon as I heard good things about it.

However I am having an annoying problem. I connected a 720p hdtv to the box and even at the grub screen I get black bars on each side of the screen. As expected, I have the same problem in gdm and gnome. I can stretch screen after loading the gnome with a script which is basically

/opt/bin/aticonfig --set-dispattrib=$DISPLAY_TYPE,positionX:34
/opt/bin/aticonfig --set-dispattrib=$DISPLAY_TYPE,positionY:20
/opt/bin/aticonfig --set-dispattrib=$DISPLAY_TYPE,sizeX:$WIDTH
/opt/bin/aticonfig --set-dispattrib=$DISPLAY_TYPE,sizeY:$HEIGHT

However this solution is annoying and I would love to have a solution for this. I do not even know if grub screen and gdm screen underscan problems are related (probably not). You may think that it is a hardware related issue but the same system and tv works fine with windows 8 without any underscan problems.

What would you suggest to me at this point.
Thanks in advance.

[aspedisca]

thanks, switching to arch expecting better support.

[Stupot]

Sorry we couldn't help. I've use ati drivers (both proprietary and open source) on my htpc connected to my 1080p tv via hdmi. The only issues I had were with overscan, but that could be corrected in the manner you spoke of (after logging into the DE) or disabling the overscan on the t.v.

Perhaps Windows 7 has ways around the underscan issue (lots of hardware vendors make sure their stuff works right with Windows but don't care about anything else).

FYI, instead of using aticonfig, you can use the amd catalyst control center which is a gui.

[aspedisca]

Hi stupod,

Actually I figured out the problem.
First problem is with Panasonic HDTV and ati drivers for linux. Somehow, ati thinks that my HDTV is a projector so it does not allow me to adjust many parameters (they are not in the gui). One of these parameter is underscan/overscan slider bar I guess. Because I could not find it where it was supposed to be. I have seen a couple of threads on google regarding this issue and I assume it is not resolved yet.

Also, when I use xrandr, I can not see HDMI as an option on the connected outputs. I believe that this is a problem with drivers as well.

I used
/opt/bin/aticonfig --set-pcs-val=MCIL,DigitalHDTVDefaultUnderscan,0

as root to resolve the issue. You can adjust the 0 parameter in the end according to your needs. Also, you may need to restart (restart xdm, modprobe module etc...) after this command to see the effects.

About the underscan in grub menus, I guess it is a KMS related issue. I did not bother to resolve this as it does not hurt much.

I hope someone will find these information useful.