Nvidia, Modelines, Overscan...8.10

[bbear1]

Are you just specifying the modeline in the xorg.conf or are you using custom EDID file? (not that it should make any difference)

Have you looked in the xlog to check that your modeline is being validated ok?

Only other thought is that older nvidia drivers (that's if you are using nvidia) needed the horizontal values to be evenly divisible by 8

If you want to provide your modeline I can try plugging into my spreadsheet and see what are the corresponding timing numbers it reports.

[Gorthaur]

Are you just specifying the modeline in the xorg.conf or are you using custom EDID file? (not that it should make any difference)

Have you looked in the xlog to check that your modeline is being validated ok?

Only other thought is that older nvidia drivers (that's if you are using nvidia) needed the horizontal values to be evenly divisible by 8

If you want to provide your modeline I can try plugging into my spreadsheet and see what are the corresponding timing numbers it reports.

BBear1 thank you for your fast response.

I'm talking about a modeline I made in the xorg.conf file. This is the file:

Section "Monitor"
Identifier "PANASONIC-TV"
Option "ExactModeTimingsDVI" "TRUE"
HorizSync 15-45
VertRefresh 59-61
modeline "720x480" 27.00 720 736 798 858 480 489 495 525 -hsync -vsync
# orig modeline "1280x720" 74.25 1280 1390 1430 1650 720 725 730 750 +hsync +vsync
modeline "1280x720" 74.25 1150 1313 1353 1650 600 713 718 750 +hsync +vsync

EndSection

Section "Screen"
Identifier "Default Screen"
Monitor "PANASONIC-TV"
Device "gForce8600MGS"

SubSection "Display"
Depth 24
Modes "1280x720"
EndSubSection

EndSection

Section "Module"
Load "glx"
EndSection

Section "Device"
Identifier "gForce8600MGS"
Driver "nvidia"
Option "NoLogo" "FALSE"
Option "UseEDID" "FALSE"
EndSection

For the TV I'm using the "1280x720" modeline.

Even though I'm reducing the value of "H2" and "H3" there is no change in the TV. The overscan in the left is the same no matter how much I change the numbers. Is weird that I correct the vertical overscan with the same method but it doesn't work for the vertical.

This is my second day with ubuntu on my PC. I've never used it before, so there are many functions I don't know how to use yet,

In the xlog file this modeline was validated.

Thank you again for your help in this matter.

[bbear1]

I cannot spot anything obvious. You are keeping the same HTotal value and the Hsync_width is still 40. Only thought is that perhaps you are violating some limit of the monitor itself and it is reverting to a default modeline, but if that was the case you would not see your modeline as validated on the Xlog.

I have read reports where the nvidia driver doesn’t always obey the users modeline, even if you add the switches like ‘ExactModeTimingsDVI’, which I see that you are already using. If that was the case then the way round it is to use a custom EDID, which is what I am doing.

One thing that might be worth trying is to dump the EDI from your monitor as sometimes the manufacturers EDID is bad. I did this by connecting my TV to my laptop (windows box) and running Moninfo (available from Powerstrip website):

http://entechtaiwan.com/util/moninfo.shtm

Alternatively you can use the nvidia-settings GUI and dump the EDID from there. You would still need to analyze the EDID (.bin/.raw) file in some program and I would still reconnect Moninfo. Note that Moninfo does have a bug with it not always reporting the vsync width correctly. But for the purposes of dumping the manufacturers data for timing limits, the program if just fine.

In the Xlog you can see the manufacturers data, or at least some of it so you may not need to use Moninfo but I found it quite a handy utility and the report is very easy to understand.

If you want to try the custom EDID method I can help you with that.

[Gorthaur]

Hello BBear1!

Even though I don't have the knowledge to do an EDID myself I would like to try it with your help. Please tell me what info is needed or has to be done in order to start.

I will try to search for EDID so at least I'm informed.

Thank you for your help.

[bbear1]

The first step is to capture the EDID from your TV, you can do this from a windows box uisng Moninfo, or from your Ubuntu box as follows ..

System -> Administration -> Nvidia X Server Settings

Go to the GPU-0 tab, then the tab for your screen (in my case DFP-0). You should see an option Acquire EDID - select this and save to a file. This is the binary/raw EDID data from your TV.

Next, load this into Monifo and check the decoded values for the timing look ok. (you can also use parse-edid on your Ubunto box if you don't have access to a windows machine to run Monino. I can't remember how much detail parse-edid gives you however).

To customize the EDID you need to load the .bin/raw file into a hex editor. I use Hex Editor Neo from:

http://www.hhdsoftware.com/

There are also hex editors for Linux, hexedit is one that you should be able to download via the Synaptic Package manager.

Before you can change the hex bytes in your hex editor you need to figure out what the new values should be and calculate the new checksum bytes for each descriptor set. I wrote an Excel spreadsheet to do this, but you can also work it out manually. For the technical details do a search for 'VESA EDID' and you should find links to the standards documents for EDID. It is a bit tricky and if you make a mistake and send invalid timing parameters to your TV it can result in damage! (most new monitors I suspect protect against damage, but I add the disclaimer here anyway)

Once you have customised your EDID in your hex editor you need to save it back to a .bin file, then modify your xorg.conf to load your custom EDID, here is an extract from my xorg.conf as an example:

Section "Monitor"
Identifier "Configured Monitor"
Option "DPMS" "false"
Option "ConnectedMonitor" "DFP"
Option "UseEDID" "TRUE"
EndSection

Section "Screen"
Identifier "Default Screen"
Monitor "Configured Monitor"
Device "Configured Video Device"
Option "AddARGBGLXVisuals" "true"
Option "UseDisplayDevice" "DFP-0"
Option "CustomEDID" "DFP-0:/etc/X11/custom_edid.bin"
DefaultDepth 24
SubSection "Display"
Depth 24
Modes "1840x1040"
EndSubSection
EndSection

Section "Module"
Load "glx"
EndSection

Section "Device"
Identifier "Configured Video Device"
Option "UseEvents" "true"
Driver "nvidia"
Option "NoLogo" "True"
EndSection

When you first load the custon EDID I suugest you enable verbose reporting for your Xlog, presumably you know how to do this? If not then I will dig out the instructions.

If you want to use my spreadsheet let me know, I can send it to you.

[bbear1]

For those who are interested, I will attach my Excel spreadsheet. In addition it needs a 3rd party plug-in to be installed, this is called 'Morefunc' and is available as a free download. It provides additional HEX functions without which would have made the spreadsheet much harder to put together.

Morefunc can be downloaded from the following site:

http://xcell05.free.fr/morefunc/english/index.htm

I wrote the spreadsheet for my personal use so there is no built-in documentation. Also, I have not built in any 'safety checks' so if you plug in some stupid numbers then it will give unexpected (but hopefully obvious) results.

The way I used is was to start my reading the EDID of my monitor using the nvidia-settings gui. Then I opened up the resulting .bin file using a binary viewer/editor. I used Hex Editor Neo on my PC, this is a great utility and is also free.

Hex Editor displays the binary data as hex bytes, and I then types these hex values into the spreadsheet. The spreadsheet then interprets the data and displays the timing values and the corresponding modeline.

In the bottom half of the spreadsheet there is a section where you can enter your own modeline, and as you type the modeline values the spreadsheet calculates the new timing values and fills in the new hex bytes and also calculates the new checksum byte which has to in the end of each descriptor block.

The spreadsheet only handles two descriptor blocks but could easily be expanded to more. The EDID for my HDTV only had two descriptor blocks in the EDID data, one for 720p and one for 1080i

After entering my custom modeline I then use Hex Editor to edit a copy of the original .bin file, I enter the new hex values calculated by the spreadsheet. After I have checked I entered the data correctly I save the .bin file and then as a sanity check I load it into Moninfo

Usually the modeline that Moninfo reports is correct but I have occasionally hit on some Vsync timing values which trigger a bug in the program. This is definitely a bug in the Moninfo program and not my spreadsheet. I confirmed this by manually checking my values against the VESA spec for EDID and also looked at the timing values as interpreted by X when it loaded my custom EDID .bin file.

Even though Moninfo has some quirks it is still a useful program to gather some data from the raw EDID (.bin) file. Monifno can be downloaded from the following location:

http://entechtaiwan.com/util/moninfo.shtm

(it is the program referred to as ‘Monitor Asset Manager’)

I will follow this post up later with some tips on how to use the spreadsheet.

[David Valentine]

Thanks for the great howto. I found a way to circumvent the iterations needed to get the right screen size if you're running mythtv. The following works for Mythbuntu 9.04.

1. Follow the directions up through generating the new modelines in /etc/X11/xorg.conf. You can probably skip the low resolution modeline as we won't use it.
2. Start MythTV. From the top menu, navigate to Utilities/Setup, then Setup, then Screen Setup Wizards.
3. Use down and right arrows while watching the upper left corner of your screen. A shaded right triangle will appear, with the right angle highlighted in white. Use your arrows to position the point of the right angle at the upper left corner of your screen. Hit enter, then do the same thing for the lower right corner of your screen.
4. Write down the Size and Offset numbers.
5. Edit /etc/X11/xorg.conf. The two Size numbers become your new H1 and V1 in your high resolution modeline. Then subtract the first offset number from both H2 and H3 to get your new H2 and H3 values. Finally, subtract the second offset number from both V2 and V3 to get your new V2 and V3 values. Save xorg.conf.
6. Restart X, and enjoy your right-sized screen.

[NateMan]

I too am having problems with nvida overscan issues. I've tried to fix my modelines and xorg.conf on my media center pc but to no avail. It appears that my xorg.conf file is not reading my modelines, since changing them seems to have no affect. Here is a copy of my xorg.conf.I would love to get this modeline problem fixed so that I can truly enjoy my newly setup ubuntu.

Thank you in advance.

[jt_04]

And you should be looking at the login screen and actually seeing the time on the bottom right!

I can't thank you enough. I roughly followed your guide and was able to get 1920x1080 with no overscan on my Sony Bravia 40" (model KDL-40S4100). I have been struggling with this for weeks.

I used your command:

X -verbose 6 > ~/xlog.txt 2>&1

to pull out the TV's modelines from the EDID info (i think I could have just looked at /var/log/Xorg.0.log too).

somehow during this I found the Nvidia X-server gui was correctly detecting that I have a 1920x1080 mode. I generated an xorg.conf file by hitting "Save to X Configuration File" in Nvidia X-Server Settings under "X Server Display Configuration". the xorg.conf file it saved had the proper 1920x1080 modeline in it, because I verified it against the output from the command above. the problem was that it was defaulting to 1024x768 because X didn't like the refresh rate of that modeline or something.

at first, i was confused because I had two screens in my xorg.conf file and I could tell which one was being used. then i read up on the xorg.conf file and figured out that the screen to be used is specified in the "ServerLayout" section. I just had to point that screen line to the right screen.

then i had to add the options

Option "ExactModeTimingsDVI" "TRUE"
Option "ModeValidation" "NoEdidModes"

to stop the X server from validating the modes against the EDID info. after that, it started in 1920x1080 just fine, with some overscan.

I knew from windows that I needed an 1824x1028 resolution to fit my TV. I modified the 1920x1080 modeline to use this resolution, which worked perfect. then I adjusted H2 H3 V2 V3 as you said to make the screen fit.

beautiful! I've now got Ubuntu 9.04 (64-bit) running on my M3N78-EM motherboard with a Nvidia 9400GT card with a HDMI connection (with audio) to my Sony Bravia 40".

here is my xorg.conf if anyone cares:

# nvidia-settings: X configuration file generated by nvidia-settings
# nvidia-settings: version 1.0 (buildd@crested) Sun Feb 1 20:25:37 UTC 2009

# nvidia-xconfig: X configuration file generated by nvidia-xconfig
# nvidia-xconfig: version 1.0 (buildmeister@builder62) Tue Mar 24 06:15:32 PST 2009

Section "ServerLayout"
Identifier "Default Layout"
# Screen 0 "Screen0" 0 0
Screen 0 "Sony Bravia KDL40S4100" 0 0
InputDevice "Keyboard0" "CoreKeyboard"
InputDevice "Mouse0" "CorePointer"
EndSection

Section "ServerFlags"
Option "Xinerama" "0"
Option "DontZap" "no"
EndSection

Section "InputDevice"

# generated from default
Identifier "Keyboard0"
Driver "keyboard"
EndSection

Section "InputDevice"

# generated from default
Identifier "Mouse0"
Driver "mouse"
Option "Protocol" "auto"
Option "Device" "/dev/psaux"
Option "Emulate3Buttons" "no"
Option "ZAxisMapping" "4 5"
EndSection

Section "Monitor"
Identifier "KDL40W4100"
HorizSync 15.0 - 70.0
VertRefresh 58.0 - 62.0
Modeline "1024x768" 65.00 1024 1048 1184 1344 768 771 777 806 -hsync -vsync
# ModeLine "1920x1080" 148.50 1919 2030 2052 2201 1080 1084 1089 1125 +hsync +vsync
ModeLine "1920x1080" 148.50 1826 1982 2004 2201 1028 1058 1063 1125 +hsync +vsync
Option "DPMS" "FALSE"
Option "DPI" "100x100"
Option "ExactModeTimingsDVI" "TRUE"
EndSection

Section "Monitor"
Identifier "Monitor0"
VendorName "Unknown"
ModelName "SONY TV"
HorizSync 15.0 - 70.0
VertRefresh 58.0 - 62.0
EndSection

Section "Device"
Identifier "Device0"
Driver "nvidia"
VendorName "NVIDIA Corporation"
BoardName "GeForce 9400 GT"
Option "ModeValidation" "NoEdidModes"
EndSection

Section "Screen"
Identifier "Sony Bravia KDL40S4100"
Device "Device0"
Monitor "KDL40W4100"
DefaultDepth 24
SubSection "Display"
Depth 24
Modes "1920x1080"
EndSubSection
EndSection

Section "Screen"
Identifier "Screen0"
Device "Device0"
Monitor "Monitor0"
DefaultDepth 24
Option "TwinView" "0"
Option "metamodes" "1920x1080_60 +0+0"
SubSection "Display"
Depth 24
EndSubSection
EndSection

[feh]

I just wanted to let the community know that the following options corrected overscan for my setup as well:

Option "ExactModeTimingsDVI" "TRUE"
Option "ModeValidation" "NoEdidModes"

I spent a week googling and trying everything under the sun to avoid the overscan on my HDTV connected to the HDMI output of an ASUS motherboard w/ a GeForce 8200 GPU on it. The above options (along with appropriate modelines) resulted in a perfectly sized screen.

Thanks!