RPiconfig

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.

The information below originally came from Dom in this forum post.

WARNING: Setting any of the parameters which over volt your Raspberry Pi will set a permanant 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 postet on the forum and are not confimed to work.

=File format=

The format is "property=value". value is an integer. One option per line. # is comment character. E.g. arm_freq=800 sdtv_mode=2 overscan_left=32 overscan_right=32 overscan_top=32 overscan_bottom=32
 * 1) hdmi_mode=19

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.

Mode values
sdtv_mode is  SDTV_MODE_NTSC       = 0, /**<Normal NTSC */ SDTV_MODE_NTSC_J    = 1, /**<Japanese version of NTSC – no pedestal.*/ SDTV_MODE_PAL       = 2, /**<Normal PAL */ SDTV_MODE_PAL_M     = 3, /**<Brazilian version of PAL – 525/60 rather than 625/50, different subcarrier */ sdtv_aspect is  SDTV_ASPECT_4_3      = 1, /**<4:3 */ SDTV_ASPECT_14_9    = 2, /**<14:9 */ SDTV_ASPECT_16_9    = 3  /**<16:9 */ hdmi_mode is (in CEA mode) HDMI_CEA_VGA            =  1, HDMI_CEA_480p60         =  2, HDMI_CEA_480p60H        =  3, HDMI_CEA_720p60         =  4, HDMI_CEA_1080i60        =  5, HDMI_CEA_480i60         =  6, HDMI_CEA_480i60H        =  7, HDMI_CEA_240p60         =  8, HDMI_CEA_240p60H        =  9, HDMI_CEA_480i60_4x      = 10, HDMI_CEA_480i60_4xH     = 11, HDMI_CEA_240p60_4x      = 12, HDMI_CEA_240p60_4xH     = 13, HDMI_CEA_480p60_2x      = 14, HDMI_CEA_480p60_2xH     = 15, HDMI_CEA_1080p60        = 16, HDMI_CEA_576p50         = 17, HDMI_CEA_576p50H        = 18, HDMI_CEA_720p50         = 19, HDMI_CEA_1080i50        = 20, HDMI_CEA_576i50         = 21, HDMI_CEA_576i50H        = 22, HDMI_CEA_288p50         = 23, HDMI_CEA_288p50H        = 24, HDMI_CEA_576i50_4x      = 25, HDMI_CEA_576i50_4xH     = 26, HDMI_CEA_288p50_4x      = 27, HDMI_CEA_288p50_4xH     = 28, HDMI_CEA_576p50_2x      = 29, HDMI_CEA_576p50_2xH     = 30, HDMI_CEA_1080p50        = 31, HDMI_CEA_1080p24        = 32, HDMI_CEA_1080p25        = 33, HDMI_CEA_1080p30        = 34, HDMI_CEA_480p60_4x      = 35, HDMI_CEA_480p60_4xH     = 36, HDMI_CEA_576p50_4x      = 37, HDMI_CEA_576p50_4xH     = 38, HDMI_CEA_1080i50_rb     = 39, HDMI_CEA_1080i100       = 40, HDMI_CEA_720p100        = 41, HDMI_CEA_576p100        = 42, HDMI_CEA_576p100H       = 43, HDMI_CEA_576i100        = 44, HDMI_CEA_576i100H       = 45, HDMI_CEA_1080i120       = 46, HDMI_CEA_720p120        = 47, HDMI_CEA_480p120        = 48, HDMI_CEA_480p120H       = 49, HDMI_CEA_480i120        = 50, HDMI_CEA_480i120H       = 51, HDMI_CEA_576p200        = 52, HDMI_CEA_576p200H       = 53, HDMI_CEA_576i200        = 54, HDMI_CEA_576i200H       = 55, HDMI_CEA_480p240        = 56, HDMI_CEA_480p240H       = 57, HDMI_CEA_480i240        = 58, HDMI_CEA_480i240H       = 59, hdmi_mode is (in DMT mode) HDMI_DMT_640x350_85 = 0x1, /**<640x350 */ HDMI_DMT_640x400_85 = 0x2, /**<640x400 */ HDMI_DMT_IBM_VGA_85 = 0x3, /**<720x400 */ HDMI_DMT_VGA_60 = 0x4, /**<640x480 (60Hz is same as VGA in CEA above) */ HDMI_DMT_VGA_72 = 0x5, HDMI_DMT_VGA_75 = 0x6, HDMI_DMT_VGA_85 = 0x7, HDMI_DMT_SVGA_56 = 0x8, /**<800x600 */ HDMI_DMT_SVGA_60 = 0x9, HDMI_DMT_SVGA_72 = 0xA, HDMI_DMT_SVGA_75 = 0xB, HDMI_DMT_SVGA_85 = 0xC, HDMI_DMT_SVGA_120 = 0xD, HDMI_DMT_848x480_60 = 0xE, /**<848x480 */ HDMI_DMT_XGA_43 = 0xF, /**<1024x768 – interlaced, DO NOT USE */ HDMI_DMT_XGA_60 = 0x10, /**<1024x768 */ HDMI_DMT_XGA_70 = 0x11, HDMI_DMT_XGA_75 = 0x12, HDMI_DMT_XGA_85 = 0x13, HDMI_DMT_XGA_120 = 0x14, HDMI_DMT_XGAP_75 = 0x15, /**<1152x864 */ HDMI_DMT_WXGA_RB = 0x16, /**<1280x768 reduced blanking */ HDMI_DMT_WXGA_60 = 0x17, HDMI_DMT_WXGA_75 = 0x18, HDMI_DMT_WXGA_85 = 0x19, HDMI_DMT_WXGA_120 = 0x1A, /**<120Hz with reduced blanking */ HDMI_DMT_1280x800_RB = 0x1B, /**<1280x800 reduced blanking */ HDMI_DMT_1280x800_60 = 0x1C, HDMI_DMT_1280x800_75 = 0x1D, HDMI_DMT_1280x800_85 = 0x1E, HDMI_DMT_1280x800_120 = 0x1F, /** reduced blanking */ HDMI_DMT_1280x960_60 = 0x20, /**<1280x960 */ HDMI_DMT_1280x960_85 = 0x21, HDMI_DMT_1280x960_120 = 0x22, /** reduced blanking */ HDMI_DMT_SXGA_60 = 0x23, /**<1280x1024 */ HDMI_DMT_SXGA_75 = 0x24, HDMI_DMT_SXGA_85 = 0x25, HDMI_DMT_SXGA_120 = 0x26, /** reduced blanking */ HDMI_DMT_1360x768_60 = 0x27, /**<1360x768 */ HDMI_DMT_1360x768_120 = 0x28, /**<120 Hz with reduced blanking */ HDMI_DMT_SXGAP_RB = 0x29, /**<1400x1050 reduced blanking */ HDMI_DMT_SXGAP_60 = 0x2A, HDMI_DMT_SXGAP_75 = 0x2B, HDMI_DMT_SXGAP_85 = 0x2C, HDMI_DMT_SXGAP_120 = 0x2D, /** reduced blanking */ HDMI_DMT_1440x900_RB = 0x2E, /**<1440x900 reduced blanking */ HDMI_DMT_1440x900_60 = 0x2F, HDMI_DMT_1440x900_75 = 0x30, HDMI_DMT_1440x900_85 = 0x31, HDMI_DMT_1440x900_120 = 0x32, /** reduced blanking */ HDMI_DMT_UXGA_60 = 0x33, /**<1600x1200 60Hz */ HDMI_DMT_UXGA_65 = 0x34, HDMI_DMT_UXGA_70 = 0x35, HDMI_DMT_UXGA_75 = 0x36, HDMI_DMT_UXGA_85 = 0x37, HDMI_DMT_UXGA_120 = 0x38, /** reduced blanking */ HDMI_DMT_SWXGAP_RB = 0x39, /**<1680x1050 reduced blanking */ HDMI_DMT_SWXGAP_60 = 0x3A, /**<1680x1050 60Hz */ HDMI_DMT_SWXGAP_75 = 0x3B, HDMI_DMT_SWXGAP_85 = 0x3C, HDMI_DMT_SWXGAP_120 = 0x3D, /** reduced blanking */ HDMI_DMT_1792x1344_60 = 0x3E, /**<1792x1344 60Hz */ HDMI_DMT_1792x1344_75 = 0x3F, /**<1792x1344 75Hz */ HDMI_DMT_1792x1344_120 = 0x40, /** reduced blanking */ HDMI_DMT_1856x1392_60 = 0x41, /**<1856x1392 60Hz */ HDMI_DMT_1856x1392_75 = 0x42, /**<1856x1392 75Hz */ HDMI_DMT_1856x1392_120 = 0x43, /** reduced blanking */ HDMI_DMT_WUXGA_RB = 0x44, /**<1920x1200 reduced blanking */ HDMI_DMT_WUXGA_60 = 0x45, /**<1920x1200 60Hz */ HDMI_DMT_WUXGA_75 = 0x46, /**<1920x1200 75Hz */ HDMI_DMT_WUXGA_85 = 0x47, /**<1920x1200 85Hz */ HDMI_DMT_WUXGA_120 = 0x48, /** reduced blanking */ HDMI_DMT_1920x1440_60 = 0x49, /**<1920x1440 60Hz */ HDMI_DMT_1920x1440_75 = 0x4A, /**<1920x1440 75Hz */ HDMI_DMT_1920x1440_120 = 0x4B, /** reduced blanking */ HDMI_DMT_2560x1600_RB = 0x4C, /**<2560x1600 reduced blanking */ HDMI_DMT_2560x1600_60 = 0x4D, /**<2560x1600 60 Hz */ HDMI_DMT_2560x1600_75 = 0x4E, /**<2560x1600 75 Hz */ HDMI_DMT_2560x1600_85 = 0x4E, /**<2560x1600 85 Hz */ HDMI_DMT_2560x1600_120 = 0x50, /** reduced blanking */ HDMI_DMT_1366x768_60 = 0x51, /**<1366x768 60Hz */ HDMI_DMT_1080p_60 = 0x52, /**<Same as 1080p60 in CEA above */ HDMI_DMT_1600x900_RB = 0x53, /**<1600x900 reduced blanking */ HDMI_DMT_2048x1152_RB = 0x54, /**<2048x1152 reduced blanking */ HDMI_DMT_720p_60 = 0x55, /**<Same as 720p60 in CEA above */ HDMI_DMT_1366x768_RB = 0x56, /**<1366x768 reduced blanking */ hdmi_drive is  HDMI_DRIVE_DVI           = 1, /**<Normal DVI mode */ HDMI_DRIVE_HDMI         = 2, /**<Normal HDMI mode */