resolution issues with hdtv

[m0s1n]

Max VGA resolution for my Toshiba Regza 40" HDTV was not offered as a choice from the display settings. After A LOT of searching and chatting on the irc, this is what i came up with:

To confirm resolutions available for my monitor, I used xrandr (as suggested by LtL from debian IRC) . As you can see, the highest supported resolution on VGA1 is 1024x768. From reading the manual for my HDTV, i KNOW 1360x768 should be supported. Houston, we have a problem.

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m0s1n@debian:~$ xrandr
Screen 0: minimum 320 x 200, current 1024 x 768, maximum 8192 x 8192
LVDS1 connected (normal left inverted right x axis y axis)
   1366x768       60.1 +
   1360x768       59.8     60.0  
   1024x768       60.0  
   800x600        60.3     56.2  
   640x480        59.9  
VGA1 connected 1024x768+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
   1024x768       60.0* 
   800x600        60.3     56.2  
   848x480        60.0  
   640x480        59.9  
HDMI1 disconnected (normal left inverted right x axis y axis)
DP1 disconnected (normal left inverted right x axis y axis)
DP2 disconnected (normal left inverted right x axis y axis)

As it turns out, the extended display identification data, or EDID, was not being sent from my tv to the computer like it should. I found this out by running sudo get-edid.

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m0s1n@debian:~$ sudo get-edid
get-edid: get-edid version 2.0.0

	Performing real mode VBE call
	Interrupt 0x10 ax=0x4f00 bx=0x0 cx=0x0
	Function supported
	Call successful

	VBE version 300
	VBE string at 0x11100 "Intel(r)Cantiga Graphics Chip Accelerated VGA BIOS"

VBE/DDC service about to be called
	Report DDC capabilities

	Performing real mode VBE call
	Interrupt 0x10 ax=0x4f15 bx=0x0 cx=0x0
	Function supported
	Call successful

	Monitor and video card combination does not support DDC1 transfers
	Monitor and video card combination does not support DDC2 transfers
	0 seconds per 128 byte EDID block transfer
	Screen is not blanked during DDC transfer

Reading next EDID block

VBE/DDC service about to be called
	Read EDID

	Performing real mode VBE call
	Interrupt 0x10 ax=0x4f15 bx=0x1 cx=0x0
	Function supported
	Call failed

The EDID data should not be trusted as the VBE call failed
Error: output block unchanged

Next, i looked at my user manual and found the list of supported VESA Standard resolutions. The one that i wanted to use was the highest available WXGA resolution of 1360x768.

In order to save yourself some typing, just run cvt. You can change this to your desired resolution if needed.

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cvt 1360 768 60

This was my output

• # 1360x768 59.80 Hz (CVT) hsync: 47.72 kHz; pclk: 84.75 MHz
  Modeline "1360x768_60.00" 84.75 1360 1432 1568 1776 768 771 781 798 -hsync +vsync

This will give you the line that xrandr needs for the --newmode option. The modeline is what you want to copy(in bold WITH quotes)

Create the new resolution with xrandr --newmode PASTE-MODE-LINE-HERE

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xrandr --newmode "1360x768_60.00" 84.75 1360 1432 1568 1776 768 771 781 798 -hsync +vsync

Now, lets add that new resolution to the list of available resolutions for VGA1 (VGA1 may be different for your setup. Check the output of xrandr for your display name)

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xrandr --addmode VGA1 "1360x768_60.00"

Now see if your new resolution works

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xrandr --output VGA1 --mode "1360x768_60.00"

I am extremely new to linux. If this article helped you, awesome. If you're still having trouble, hopefully someone smarter than me can help you figure it out because I will be completely useless. This article was written because of how long it took me to find my answer. It was written by me for my own reference in the future.

keywords: hdtv, resolution, vga, wxga, vesa, xrandr, vide,o display, toshiba regza 40" 40ux600u, Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller (rev 09),