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whoops

Member

Registered: 2009-03-19

Posts: 891

[solved] nvidia: "overscan" on lcd (wrong edid / hdmi?)

Hi!

I don't get it how that's even possible: I have a huge "overscan" with my nvidia card / lcd monitor. Using the overscan compensation to see the full image of course results in a quite blurry and headache-inducing experience so please forgive me if I haven't done all my "homework".

nvidia-settings says:
connection link: DUAL
Signal: TMDS
Native/Best/Frontend/Backend Resolution: All of them 1920x1200
force gpu scaling is activated
scaling: none
I need to set the overscan compensation to about 136 so I see my full desktop.

If I set my monitor's image adjustment / scaling method to "1:1" (instead of "fullscreen), I get a smaller screen but the edges are still cut off which makes me think that my graphics card is not actually sending the resolution it's pretending to send. I don't get it... at all... all I can find on problems like this suggests that setting scaling method to 1:1 should solve the problem.

After closing xserver, this problem persists in tty. Also for other users.

Help? Thanks!

Last edited by whoops (2011-08-14 08:25:21)

jackdroido

Member

From: Italy

Registered: 2011-07-26

Posts: 8

Re: [solved] nvidia: "overscan" on lcd (wrong edid / hdmi?)

Hi !

Try to see the various solutions which I posted here: https://bbs.archlinux.org/viewtopic.php?id=121947

I have an Nvidia ION board connected to a TV via HDMI.

I initially tried to use the Nvidia control panel but the result was the same as your, a strange "out-of-focus" image, so I go the hard way

Hope it help !

whoops

Member

Registered: 2009-03-19

Posts: 891

Re: [solved] nvidia: "overscan" on lcd (wrong edid / hdmi?)

Thanks, but didn't get any further with that... trying to ignore edid in any way / set manual modelines only got me to a resolution a lot to low, not the native one. T

After disabling nvidia driver, at least I can look at the screen without getting dizzy, so I found some stuff:

Possible explanation:
http://nvidia.custhelp.com/app/answers/detail/a_id/2153

fix that doesn't work for me (german, but relevant xorg.conf in last post):
http://forum.ubuntuusers.de/topic/deskt … st-2979872

more of the same stuff that didn't work:
http://www.ypass.net/blog/2009/07/dvi-t … n-an-hdtv/

and a different (edid) fix. Either the tools provided or the method don't work, can't tell:
http://analogbit.com/fix_nvidia_edid

Now that I can write & look up stuff without getting dizzy again, some more info:
- Problem occured after I got a new graphics card.
- Using a GeForce GTX 560 Ti now
- Monitor: ViewSonic VX2835wm
- Everything worked before with a geforce 7800gts (or something like that) card. (maybe because that old card doesn't dupport hdmi?)

What I'm planning to do next / tomorrow is: Use the old graphics card to extract the "dvi edid" and then override the "hdmi edid" with that using xorg.conf / custom edid file... if someone here knows I'm going the wrong way with that or has a better idea to try first, please stop me: that'll be a lot of moving around stuff heavy & fragile stuff.

edit:
Found someone who uploaded a modified edid here:
http://ubuntuforums.org/showthread.php?t=1611913
Using it as override didn't chance anything. Maybe I'm way off and that has nothing to do with my problem?

Last edited by whoops (2011-08-12 21:54:30)

whoops

Member

Registered: 2009-03-19

Posts: 891

Re: [solved] nvidia: "overscan" on lcd (wrong edid / hdmi?)

I think I somehow managed to remove the audio channel from what the graphics card is submitting and now it's sort of working, as long as I don't try to chance the resolution. I'm not really sure how... have some strange configurations around now most of which most likely are not needed (and break other stuff). Going to try to figure it out after I've enjoyed the working screen a bit, don't want to break it again right away.

jackdroido

Member

From: Italy

Registered: 2011-07-26

Posts: 8

Re: [solved] nvidia: "overscan" on lcd (wrong edid / hdmi?)

I have once also tried the custom EDID trick (using the edid_disable_exts tool you mentioned above) and image was perfect.

But with this method (as you note) I was losing audio through HDMI (and I absolutely wanted it) so I fallback into the modelines nightmare

So, if you don't care audio throught HDMI, this is a nice solution after all.

whoops

Member

Registered: 2009-03-19

Posts: 891

Re: [solved] nvidia: "overscan" on lcd (wrong edid / hdmi?)

Did you find a "modelines solution"? I'm not sure how I managed to get that EDID working (the tool mentioned gave me something absolutely broken at first, so I did more... stuff) and I'd rather get rid of some "strange files I don't unterstand", so if there's a xorg-conf only solution: that would be a lot less... scary.

whoops

Member

Registered: 2009-03-19

Posts: 891

Re: [solved] nvidia: "overscan" on lcd (wrong edid / hdmi?)

So: I guess I eliminated all the redundant steps (I tried a LOT of strange / stupid stuff ) and "my" solution looked like this:

- Compile the tool available  there: http://analogbit.com/fix_nvidia_edid (the precompiled version didn't seem to work for me)
- extract your edid ("aquire edid") with nvidia-settings
- use the tool with that "--remove-audio-only-option" (--help for the real name of that option. Without the option, it didn't work for me)
- add an option to the DEVICE section of the nvidia card (xorg.conf or xorg.conf.d) like: Option "CustomEDID" "DFP-0:/etc/X11/edid-modified.bin"
- See to it, that your monitor is recognized as DFP-0 (don't know why, but just changing the option line to "DFP-X" instead didn't work ) somehow

Last edited by whoops (2011-08-14 08:26:22)