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Revision as of 01:46, 20 May 2012 by Bredman (talk | contribs) (Which values are valid for my monitor?)
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The Raspberry Pi config.txt file is read by the GPU before the ARM core is initialised. It can be used to set various system configuration parameters.

This file is an optional file on the boot partition. It would normally be accessible as /boot/config.txt from Linux.

To edit the configuration file, see the instructions at R-Pi_ConfigurationFile.

File format

The format is "property=value". value is an integer. You may specify only one option per line. Comments may be added by starting a line with the '#' character.

Here is an example file

# Set stdv mode to PAL (as used in Europe)
# Force the monitor to HDMI mode so that sound will be sent over HDMI cable
# Set monitor mode to DMT
# Set monitor resolution to 1024x768 XGA 60Hz (HDMI_DMT_XGA_60)
# Make display smaller to stop text spilling off the screen

Video mode configuration

Video mode options

sdtv_mode defines the TV standard for composite output (default=0)

sdtv_mode=0    Normal NTSC
sdtv_mode=1    Japanese version of NTSC – no pedestal
sdtv_mode=2    Normal PAL
sdtv_mode=3    Brazilian version of PAL – 525/60 rather than 625/50, different subcarrier

sdtv_aspect defines the aspect ratio for composite output (default=1)

sdtv_aspect=1  4:3
sdtv_aspect=2  14:9
sdtv_aspect=3  16:9

hdmi_drive chooses between HDMI and DVI modes

 hdmi_drive= 1 Normal DVI mode (No sound)
 hdmi_drive= 2 Normal HDMI mode (Sound will be sent if supported and enabled)

hdmi_group defines the HDMI type (default=1)

hdmi_group=1   CEA
hdmi_group=2   DMT

hdmi_mode defines screen resolution in CEA or DMT format

These values are valid if hdmi_group=1 (CEA)
hdmi_mode=1    VGA
hdmi_mode=2    480p  60
hdmi_mode=3    480p  60  H
hdmi_mode=4    720p  60
hdmi_mode=5    1080i 60
hdmi_mode=6    480i  60
hdmi_mode=7    480i  60  H
hdmi_mode=8    240p  60
hdmi_mode=9    240p  60  H
hdmi_mode=10   480i  60  4x
hdmi_mode=11   480i  60  4x H
hdmi_mode=12   240p  60  4x
hdmi_mode=13   240p  60  4x H
hdmi_mode=14   480p  60  2x
hdmi_mode=15   480p  60  2x H
hdmi_mode=16   1080p 60
hdmi_mode=17   576p  50
hdmi_mode=18   576p  50  H
hdmi_mode=19   720p  50
hdmi_mode=20   1080i 50
hdmi_mode=21   576i  50
hdmi_mode=22   576i  50  H
hdmi_mode=23   288p  50
hdmi_mode=24   288p  50  H
hdmi_mode=25   576i  50  4x
hdmi_mode=26   576i  50  4x H
hdmi_mode=27   288p  50  4x
hdmi_mode=28   288p  50  4x H
hdmi_mode=29   576p  50  2x
hdmi_mode=30   576p  50  2x H
hdmi_mode=31   1080p 50
hdmi_mode=32   1080p 24
hdmi_mode=33   1080p 25
hdmi_mode=34   1080p 30
hdmi_mode=35   480p  60  4x
hdmi_mode=36   480p  60  4xH
hdmi_mode=37   576p  50  4x
hdmi_mode=38   576p  50  4x H
hdmi_mode=39   1080i 50  reduced blanking
hdmi_mode=40   1080i 100
hdmi_mode=41   720p  100
hdmi_mode=42   576p  100
hdmi_mode=43   576p  100 H
hdmi_mode=44   576i  100
hdmi_mode=45   576i  100 H
hdmi_mode=46   1080i 120
hdmi_mode=47   720p  120
hdmi_mode=48   480p  120
hdmi_mode=49   480p  120 H
hdmi_mode=50   480i  120
hdmi_mode=51   480i  120 H
hdmi_mode=52   576p  200
hdmi_mode=53   576p  200 H
hdmi_mode=54   576i  200
hdmi_mode=55   576i  200 H
hdmi_mode=56   480p  240
hdmi_mode=57   480p  240 H
hdmi_mode=58   480i  240
hdmi_mode=59   480i  240 H
These values are valid if hdmi_group=2 (DMT)
hdmi_mode=1    640x350   85
hdmi_mode=2    640x400   85
hdmi_mode=3    720x400   85
hdmi_mode=4    640x480   60
hdmi_mode=5    640x480   72
hdmi_mode=6    640x480   75
hdmi_mode=7    640x480   85
hdmi_mode=8    800x600   56
hdmi_mode=9    800x600   60
hdmi_mode=10   800x600   72
hdmi_mode=11   800x600   75
hdmi_mode=12   800x600   85
hdmi_mode=13   800x600   120
hdmi_mode=14   848x480   60
hdmi_mode=15   1024x768  43  DO NOT USE
hdmi_mode=16   1024x768  60
hdmi_mode=17   1024x768  70
hdmi_mode=18   1024x768  75
hdmi_mode=19   1024x768  85
hdmi_mode=20   1024x768  120
hdmi_mode=21   1152x864  75
hdmi_mode=22   1280x768      reduced blanking
hdmi_mode=23   1280x768  60
hdmi_mode=24   1280x768  75
hdmi_mode=25   1280x768  85
hdmi_mode=26   1280x768  120 reduced blanking
hdmi_mode=27   1280x800      reduced blanking
hdmi_mode=28   1280x800  60
hdmi_mode=29   1280x800  75
hdmi_mode=30   1280x800  85
hdmi_mode=31   1280x800  120 reduced blanking
hdmi_mode=32   1280x960  60
hdmi_mode=33   1280x960  85
hdmi_mode=34   1280x960  120 reduced blanking
hdmi_mode=35   1280x1024 60
hdmi_mode=36   1280x1024 75
hdmi_mode=37   1280x1024 85
hdmi_mode=38   1280x1024 120 reduced blanking
hdmi_mode=39   1360x768  60
hdmi_mode=40   1360x768  120 reduced blanking
hdmi_mode=41   1400x1050     reduced blanking
hdmi_mode=42   1400x1050 60
hdmi_mode=43   1400x1050 75
hdmi_mode=44   1400x1050 85
hdmi_mode=45   1400x1050 120 reduced blanking
hdmi_mode=46   1440x900      reduced blanking
hdmi_mode=47   1440x900  60
hdmi_mode=48   1440x900  75
hdmi_mode=49   1440x900  85
hdmi_mode=50   1440x900  120 reduced blanking
hdmi_mode=51   1600x1200 60
hdmi_mode=52   1600x1200 65
hdmi_mode=53   1600x1200 70
hdmi_mode=54   1600x1200 75
hdmi_mode=55   1600x1200 85
hdmi_mode=56   1600x1200 120 reduced blanking
hdmi_mode=57   1680x1050     reduced blanking
hdmi_mode=58   1680x1050 60
hdmi_mode=59   1680x1050 75
hdmi_mode=60   1680x1050 85
hdmi_mode=61   1680x1050 120 reduced blanking
hdmi_mode=62   1792x1344 60
hdmi_mode=63   1792x1344 75
hdmi_mode=64   1792x1344 120 reduced blanking
hdmi_mode=65   1856x1392 60
hdmi_mode=66   1856x1392 75
hdmi_mode=67   1856x1392 120 reduced blanking
hdmi_mode=68   1920x1200     reduced blanking
hdmi_mode=69   1920x1200 60
hdmi_mode=70   1920x1200 75
hdmi_mode=71   1920x1200 85
hdmi_mode=72   1920x1200 120 reduced blanking
hdmi_mode=73   1920x1440 60
hdmi_mode=74   1920x1440 75
hdmi_mode=75   1920x1440 120 reduced blanking
hdmi_mode=76   2560x1600     reduced blanking
hdmi_mode=77   2560x1600 60
hdmi_mode=78   2560x1600 75
hdmi_mode=79   2560x1600 85
hdmi_mode=80   2560x1600 120 reduced blanking
hdmi_mode=81   1366x768  60
hdmi_mode=82   1080p_60
hdmi_mode=83   1600x900      reduced blanking
hdmi_mode=84   2048x1152     reduced blanking
hdmi_mode=85   720p_60
hdmi_mode=86   1366x768      reduced blanking

overscan_left number of pixels to skip on left

overscan_right number of pixels to skip on right

overscan_top number of pixels to skip on top

overscan_bottom number of pixels to skip on bottom

framebuffer_width console framebuffer width in pixels. Default matches display.

framebuffer_height console framebuffer height in pixels. Default matches display.

test_mode enable test sound/image during boot for manufacturing test.

enable_l2cache enable arm access to GPU's L2 cache. Needs corresponding L2 enabled kernel. Default is 0.

disable_overscan set to 1 to disable overscan.

hdmi_force_hot_plug force your TV to allow hot plugging of RPi.

Which values are valid for my monitor?

Your HDMI monitor may support only a limited set of formats. To find out which formats are supported, use the following method.

  • Set the output format to VGA 60Hz (hdmi_group=1 hdmi_mode=1) and boot up the Raspberry Pi
  • Enter the following command to give a list of CEA supported modes
/opt/vc/bin/tvservice –m CEA
  • Enter the following command to give a list of DMT supported modes
/opt/vc/bin/tvservice –m DMT
  • Enter the following command to show your current state
/opt/vc/bin/tvservice -s

Overclocking configuration

WARNING: Setting any of the parameters which over volt your Raspberry Pi will set a permanent bit within the SOC and your warranty is void. So If you care about the warranty do not adjust voltage.

Also at your own risk you can try overscan settings from our wiki. These were posted on the forum and are not confimed to work.

Overclocking options

Option Description
arm_freq frequency of ARM in MHz. Default 700.
gpu_freq Sets core_freq, h264_freq, isp_freq, v3d_freq together.
core_freq frequency of GPU processor core in MHz. Default 250.
h264_freq frequency of hardware video block in MHz. Default 250.
isp_freq frequency of image sensor pipeline block in MHz. Default 250.
v3d_freq frequency of 3D block in MHz. Default 250.
sdram_freq frequency of SDRAM in MHz. Default 400.
over_voltage ARM/GPU core voltage adjust. [-16,8] equates to [0.8V,1.4V] with 0.25V steps. Default 0 (1.2V) [1]
over_voltage_sdram Sets over_voltage_sdram_c, over_voltage_sdram_i, over_voltage_sdram_p together
over_voltage_sdram_c SDRAM controller voltage adjust. [-16,8] equates to [0.8V,1.4V] with 0.25V steps. Default 0 (1.2V) [1]
over_voltage_sdram_i SDRAM I/O voltage adjust. [-16,8] equates to [0.8V,1.4V] with 0.25V steps. Default 0 (1.2V)[1]
over_voltage_sdram_p SDRAM phy voltage adjust. [-16,8] equates to [0.8V,1.4V] with 0.25V steps. Default 0 (1.2V)[1]

Tested values

The following table shows some successfull attempts of overclocking. These settings may not work on every device and can shorten the life of the Broadcom SoC. Warranty will be voided if overvoltage is used.

arm_freq gpu_freq core_freq h264_freq isp_freq v3d_freq sdram_freq over_voltage over_voltage_sdram
900 350
1000 6



  1. 1.0 1.1 1.2 1.3 What this means is that you can specify -16 and expect about 0.8V as the GPU/core voltage. This is 0.4V below the normal value of 1.2. If you specify 16, you'd get 0.4V ABOVE the normal value of 1.2V, or 1.6V. The fact that someone carefully specified "8" and "1.4V" as the upper limit in the examples leads me to think that it is likely to shorten the life of your raspberry pi significantly if you would specify values above "8". So: don't specify values above zero, but if you do, don't go above 8.