Connecting laptop to LCD TV using HDMI

Question

I have a TV and I would like to connect my Ubuntu 14.04 laptop to it via HDMI. When I connect HDMI cables between both devices I see am able to detect both devices in my display settings in Ubuntu. But on the TV I see nothing.

$ xrandr
Screen 0: minimum 320 x 200, current 2390 x 768, maximum 32767 x 32767
LVDS1 connected primary 1366x768+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
1366x768       59.9*+
1360x768       59.8     60.0  
1024x768       60.0  
800x600        60.3     56.2  
640x480        59.9  
VGA1 disconnected (normal left inverted right x axis y axis)
HDMI1 connected 1024x768+1366+0 (normal left inverted right x axis y axis) 500mm x 375mm
1024x768       75.0*+   60.0  
1920x1080i     60.1     50.0     60.0  
1280x720       60.0     50.0     59.9  
800x600        60.3  
720x576        50.0  
720x480        60.0     59.9  
640x480        75.0     60.0     59.9  
DP1 disconnected (normal left inverted right x axis y axis)
VIRTUAL1 disconnected (normal left inverted right x axis y axis)

Have also tried

xrandr --output HMDI1 --auto

the command executes with no warning, but nothing happens to the TV screen; it's still blue and displaying 'No Signal'.

I was following the instructions here on Ubuntu forums and tried the command but found this error

$ xrandr --output TMDS-1 --auto
warning: output TMDS-1 not found; ignoring

Video card info

 *-display               
   description: VGA compatible controller
   product: Core Processor Integrated Graphics Controller
   vendor: Intel Corporation
   physical id: 2
   bus info: pci@0000:00:02.0
   version: 02
   width: 64 bits
   clock: 33MHz
   capabilities: msi pm vga_controller bus_master cap_list rom
   configuration: driver=i915 latency=0
   resources: irq:42 memory:f0000000-f03fffff memory:e0000000-efffffff ioport:e080(size=8)

How can I get it working?

Solution

Your TV might be advertising a mode 1024x768 that it is not able to show.

You can use one of these commands to see if your TV can show the other modes:

xrandr --output HDMI1 --mode 1920x1080i
xrandr --output HDMI1 --mode 1280x720
xrandr --output HDMI1 --mode 1024x768 --rate 60

Comments

[Katu]

What do you see on your TV? Does it detect the hdmi and change to that channel automatically? Is it blue or black? Have you tried moving the mouse in case is been added as an extension of you laptop to the right or left?

[Umar]

on TV it says 'No Signal' and its blue, but All Settings/Displays in Ubuntu settings the TV is detected and I didn't understand last part of you question .. 'moving mouse in case is been added as an extension of laptop'.. if you mean dragging the mouse to tv .. yes I have done it.. nothing happening

[elmicha]

Can you please add the output of xrandr to your question? You should get two displays that are "connected". Try these displays in your xrandr command, e.g. xrandr --output HDMI3 --auto.

[Umar]

@elmicha, this is the output, I get a warning message umar@umar-VPCEB11FM:~$ xrandr --output HDMI3 --auto warning: output HDMI3 not found; ignoring

[elmicha]

Ok, but please show the output of xrandr alone, without any options.

[Umar]

@elmicha, I have updated the output of xrandr in the question also with me , xrandr --output HDMI1 --auto gives no warning message, but still nothing happens at tv screen. Still bule with NO Signal

[elmicha]

Your TV might be advertising a mode 1024x768 that it is not able to show. If you try xrandr --output HDMI1 --mode 1920x1080i or xrandr --output HDMI1 --mode 1280x720, do you get a signal?

[Umar]

@elmicha, I am getting signal now with both of these commands, a bit better from xrandr --output HDMI1 --mode 1280x720, I think now I have to make resolution a bit small

[Umar]

@elmicha, its working now but quality is too bad... any idea what to do in that case

[elmicha]

Let us continue this discussion in chat.