Xorg fix for Grunding Cinaro

I have a Grunding Cinaro. It is a quite old television that happens to have an HDMI input. I think it’s a 576p or 720p HDMI input.

The specific Grunding model is: GRUNDING Cinaro 32 LXW 82-6612 REF .

Anyways the specific fix is not HDMI but for its VGA input.

This television has a PC source input which enables you to connect an VGA cable plus a 3.5 mm audio jack into it.

 

I have an small PC which I connect thanks to VGA to it.

The 1024×768 mode seem to work fine.

 

The 1280×720 mode at 60  Hz which would match some high quality output does not work ok.

The screen happens to moved to the right or the left and you miss part of your PC desktop on your television output.

 

As far as I concluded this comes from a wrong EDID announcement.

It seems that when a PC is connected to a device which offers a VGA port then the device announces the different modes with its sizes, resolutions, positions, etc.

And this announcement uses the EDID standard.

 

Well, let’s check what wikipedia says about EDID.

Extended Display Identification Data (EDID) is a metadata format for display devices to describe their capabilities to a video source (e.g. graphics card or set-top box). The data format is defined by a standard published by the Video Electronics Standards Association (VESA).

The EDID data structure includes manufacturer name and serial number, product type, phosphor or filter type, timings supported by the display, display size, luminance data and (for digital displays only) pixel mapping data.

 

So, now, you know.

How do you fix your output to use Grunding Cinaro to its full potential from its VGA port?

 

Here there is an script that it is run once I log in to my desktop.

#!/bin/bash                                                                                                                                                                                                                                                                             
# 60 Hz                                                                                                                                                                                                                                                                                    
xrandr --newmode "1280x720_60.00" 74.48  1280 1336 1472 1664  720 721 724 746  -HSync +Vsync
xrandr --addmode VGA-1 1280x720_60.00
xrandr --output VGA-1 --mode 1280x720_60.00
# 75 Hz
#xrandr --newmode "1280x720_75.00" 95.65  1280 1352 1488 1696  720 721 724 752  -HSync +Vsync
#xrandr --addmode VGA-1 1280x720_75.00
#xrandr --output VGA-1 --mode 1280x720_75.00

 

As you might guess 1280×720 at 75Hz does not work so well. 1280×720 at 60Hz is fine for me.

 

Enjoy!