Raspberry Pi HDMI display spills off the screen or is cut off

Display

Startx fails to start

If you just get errors instead of a desktop when typing

 startx

you may be out of storage space on the SD card. By default there are only a few hundred MB free in the 2 GB main partition, which can quickly fill up if you download files. Make sure there is some space free (gparted can expand a partition, if the SD card is > 2GB). Also, installing some software may incorrectly create or modify a .Xauthority file in your home directory, causing startx to fail, according to this thread. Temporarily renaming, moving, or deleting that file may fix the problem.

Video does not play or plays very slowly

The only hardware-accelerated video player is in the XBMC distribution and its command line variant omxplayer. H264 is the only hardware-accelerated codec, for playback. No hardware encoding is supported. Additional codecs were not purchased as licensing fees would have increased the R-Pi’s price.

Can only get 800×480 resolution in LXDE (Arch linux)

Known issue with distro package as of 17th April 2012 – there’s some missing boot config information. Creating a suitable cmdline.txt fixes it – type the following at the Raspberry Pi command line:

  sudo echo "dwc_otg.lpm_enable=0 console=ttyAMA0,115200 kgdboc=ttyAMA0,115200 root=/dev/mmcblk0p2 rootfstype=ext3 rootwait" >/boot/cmdline.txt

Big black borders around small image on HD monitors

Out of the box, R-Pi graphics don’t necessarily fill the whole screen. This is due to something called “Underscan”, and it can be fixed easily.

Note: the best solution is to disable overscan in display menu options (it may be called “just scan”, “screen fit”, “HD size”, “full pixel”, “unscaled”, “dot by dot”, “native” or “1:1”), then use the disable_overscan=1 option.

Edit the configuration file, see the instructions at R-Pi_ConfigurationFile.

Add the following lines to the configuration file…

If your display has no overscan:

disable_overscan=1

or if your display has some overscan:

overscan_left=-20

overscan_right=-20

overscan_top=-20

overscan_bottom=-20

Making the R-Pi graphics fill the screen is a matter of experimenting with the numbers you put in the config.txt file. Change the numbers – try jumps of 5 or 10 at a time. Bigger negative numbers reduce the black borders (so -40 means less black border than -20). The numbers do not all have to be the same; you can use this feature to centre the display on the screen.

Writing spills off the screen on HD monitors

Out of the box, R-Pi graphics may be larger than the 1080p (ie Full HD) screen. This is due to something called “Overscan”, and it can be fixed easily by creating a simple text file on the R-Pi SD card by using Notepad on your PC.

Follow the instructions in the section “Big black borders around small image on HD monitors”, but use positive numbers for the overscan settings, for example

overscan_left=20

overscan_right=20

overscan_top=20

overscan_bottom=20

Interference visible on a HDMI or DVI monitor

This may be caused by loss of signal on long video cables. The signal level may be increased by changing a configuration parameter.

RPi HDMI interference.jpg

Edit the configuration file, see the instructions at R-Pi_ConfigurationFile.

Add the following line to the configuration file

config_hdmi_boost=4

You may experiment with different values of config_hdmi_boost. Value 1 is used for very short cables, value 7 is used for very long cables.

This option can also help when there is no display output at all, the display periodically blanks, or colours are wrong/inverted.

This symptom can also be caused by RasPi +5V (measured from TP1 to TP2) falling too low. See “Troubleshooting Power Problems”.

No HDMI output at all

First make sure the display is powered on and switched to the right input before booting Pi.

If you have the Wheezy image (recommended) then try

hdmi_safe=1

Otherwise, try adding the following line to the configuration file (similar to interference case above)

config_hdmi_boost=4

Your monitor/cable may not be asserting the hotplug signal. You can override this with:

hdmi_force_hotplug=1

Also try the following video options:

hdmi_group=2
hdmi_mode=4

which resolved an issue with DVI monitor reporting “input signal out of range”

As a last resort, try deleting (rename to keep backup) config.txt from the SD card.

Also check that the RasPi +5V voltage (measured from TP1 to TP2) is in the correct range. One user found that his DVI-D monitor blanked out when +5V was too low. See “Troubleshooting Power Problems”.

Composite displays only back and white or no image

Remember, the output display will be HDMI if detected, and composite if not. Make sure there isn’t a HDMI cable connected when you are wanting composite output.

We default to NTSC output. Most TVs will show an image with that, but if not:

Edit the configuration file, see the instructions at R-Pi_ConfigurationFile.

Add the following line to the configuration file

sdtv_mode=2

(You can try other values: 0 is NTSC, 1 is Japanese NTSC, 2 is PAL, 3 is Brazilian PAL)

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