Raspbmc Overvolting Guide

!!!Don’t forget to enter our Raspberry Pi Raffle!!!

Raspbmc Overvolting Guide

This guide assume that you have Putty on your computer and that you know how to connect to Raspbmc via SSH. If you you do not, please refer to HTPCBuild.com Connecting to Raspbmc via SSH Guide.

You’ve decided that you want to overclock your Raspbmc distro, but you are running into a wall. You just can’t get the MHz you want. We’ll We’ll need to use Putty to connect to your Raspberry Pi and edit the “config.txt” file.

NOTE: Overvolting your Raspberry Pi WILL void your warranty. HTPCBuild.com is not responsible for any damage that might occur when attempting to overvolt your Raspberry Pi.

1. First connect to your Raspbmc Raspberry Pi via Putty SSH.

2. Now we need to locate the “config.txt” inside of your Raspbmc distro. The “config.txt” file is located inside the boot directory. To move into the boot directory execute the following command:

cd /boot
The terminal will now show it has enter the boot directory.
3. Now you are in the boot directory. You can quickly check to make sure the “config.txt” file is inside of this directory by executing the following command:
dir
The terminal will echo back the contents of the boot directory. Here we see that the boot directory contains a file “config.txt”.

4. Now we can open up the “config.txt” file. Here we will adjust different clock parameters or add parameters if needed. To open the “config.txt” file execut the following command:

sudo nano config.txt

5. A text editor will launch and display the contents of the file “config.txt”.

6. Here comes the fun part! Here we can enter parameters we wish to add to the “config.txt” or we can adjust parameters already in it. There are a few volt values that you can adjust for your Raspberry Pi:

  • over_voltage  – Sets the voltage for the ARM and GPU processor. The default value is 0. The value range is -16 to 8. For each positive value increment you step the voltage by 0.025V. For each negative value increment you step the voltage by 0.025V. The default voltage is 1.2V, with a range of 0.8V to 1.4V.
  • over_voltage_sdram – Sets the voltage for over_voltage_sdram_c, over_voltage_sdram_i, over_voltage_sdram_p simultaneously. The default value is 0.  The value range is -16 to 8. For each positive value increment you step the voltage by 0.025v. For each negative value increment you step the voltage by 0.025v. The default voltage is 1.2V, with a range of 0.8V to 1.4V.
  • over_voltage_sdram_c – Sets the voltage for the SDRAM controller. The default value is 0. The value range is -16 to 8. For each positive value increment you step the voltage by 0.025V. For each negative value increment you step the voltage by 0.025V. The default voltage is 1.2V, with a range of 0.8V to 1.4V.
  • over_voltage_sdram_i –  Sets the voltage for SDRAM’s  I/O. The default value is 0. The value range is -16 to 8. For each positive value increment you step the voltage by 0.025V. For each negative value increment you step the voltage by 0.025V. The default voltage is 1.2V, with a range of 0.8V to 1.4V.
  • over_voltage_sdram_p – Sets the phystical voltage for theSDRAM. The default value is 0. The value range is -16 to 8. For each positive value increment you step the voltage by 0.025V. For each negative value increment you step the voltage by 0.025V. The default voltage is 1.2V, with a range of 0.8V to 1.4V.

NOTE: over_voltage_sdram controls three values simultaneously. If you wish to control these values independent of one another, you’ll need to disable over_voltage_sdram and enable the values for over_voltage_sdram_cover_voltage_sdram_i, and over_voltage_sdram_p.

NOTE: There are two ways to deactivate a volt parameter, you can either completely delete the value from your config.txt or place a “#” in front of the parameter you wish to disable. Placing a “#” indicates that the corresponding line of code is a comment and will not be executed.

7. We can see that Raspbmc by default has no overvolting parameters. You can add the over_voltage  parameter to set an overvolt on the Raspberry Pi. Changing the value of over_voltage  will set an overvolt on the next boot. Here the value is set to 1, which will overvolt the Raspbmc Raspberry Pi’s ARM & GPU to 1.225 on the next reboot.

8. To add another parameter that is not in the “config.txt” file simply enter it in a new line. Here the parameter over_voltage_sdram as been added and set to 1. This bumps the voltage for over_voltage_sdram_cover_voltage_sdram_i, and over_voltage_sdram_p  to 1.225 on the next  reboot.

NOTE: over_voltage_sdram controls three values simultaneously. If you wish to control these values independent of one another, you’ll need to disable over_voltage_sdram and enable the values for over_voltage_sdram_cover_voltage_sdram_i, and over_voltage_sdram_p.

9. When you’ve feel satisfied with your additions and changes, hit “Ctrl+O”. A small line will pop up near the bottom of the terminal asking you to name the file. Keep the same “config.txt” name and overwrite the current file.

10. To exit out of the text editor hit “Ctrl”+”X”.

11. Now reboot your Raspberry Pi, and the new settings will take effect! You can execute a reboot by typing the following command:

sudo reboot

That’s it, you’ve overvolted your Raspbmc Raspberry Pi. Please make sure to take care when overvolting your Raspberry Pi. Make changes slowly and in small increments. By making subtle changes and testing your Pi you will be able to notice as the system becomes more and more unstable. Look for signs such as random an inability to boot, random freezing, random errors. If you encounter these, SSH into your Pi and back down on the settings.