Not enough juice? Shrink your Raspberry Pi by overclocking

If there’s any piece of hardware in 2012 that you’re likely to fall in love with, it’s the Raspberry Pi, a sugar-sweet mini computer designed and built in the UK that ships all over the world. Equipped with an ARM processor and capable of running a variety of operating systems (although best results are achieved with a particularly useful Debian build), the Raspberry Pi is small enough to fit in a cigarette box and powerful enough to run a home server, media center, and more.

However, some of these uses could benefit from some extra power — the Raspberry Pi’s «juice» you might say…

Raspberry Pi Hardware

The Raspberry Pi comes with the bare minimum needed to make a usable computer — how else do you think they can make it so small?!

In addition to 256 MB of RAM, the computer is equipped with an ARM11 processor clocked at 700 MHz. This may seem insignificant compared to devices built on AMD and Intel chipsets, but the beauty of the Raspberry Pi lies in its flexibility, not its power. It is this flexibility that makes it easy to overclock. Please note that later versions have increased RAM and more ports and connectivity.

What you need to do to overclock your Raspberry Pi

To overclock your Whiz-Bang micro PC, you first need to install the Raspbian operating system (based on the popular Debian OS). Our previous guide will help you do just that.

If you’ve had a Pi for a while and have been using Raspbian during that time (or downloaded the version referenced in our previous guide), you’ll need to update Raspi-config to add new features to the configuration program. Do this on the command line by typing:

  sudo apt-get update && sudo apt-get install raspberrypi * raspi-config

This essentially updates the firmware of the device. Once you’re done, reboot your Pi and run Raspi-config. This program will allow you to set various options. one of which allows overclocking.

To overclock, select the appropriate option from the Raspi-config menu, and then make your choice from the displayed clock speeds, as shown in the figure.

Note that it is also possible to overclock your Raspberry Pi by creating a config.txt file. Recommended if for some reason you don’t want to update Raspbian OS. Use Notepad++ to change the config file on your Windows machine, available here.

overclocking raspberry pi

Once installed and downloaded, open » Preferences > Preferences > New Document/Default Directory and set the radio button UNIX «. Click close, and then click CTRL+N to start a new file. Add the following to the file:

  carm_freq = 800
 gpu_freq = 300
 sdram_freq = 450

This set of instructions will boost the processor to 800 MHz. All you have to do is change carm_freq = to overclock the processor! Now all you have to do is save the file as config.txt and store it in the boot partition on your Raspberry Pi’s SD card (60MB partition accessible from Windows).

Help, my Raspberry Pi won’t boot!

Unfortunately, if you set the clock too high, your mini computer won’t be able to boot. Don’t worry though, this can be overcome by resetting your overclock.

overclocking raspberry pi

To do this, while booting up your Raspberry Pi, hold down the SHIFT key on your keyboard. You must then run Raspi-config again to set the boot to a lower one.

If you have used the method config.txt and your computer won’t boot, edit the file to set a lower clock speed.

The official Raspberry Pi website suggests that running Quake 3 might be a good test to see if your chosen clock speed is suitable and stable. Please note that if the Raspberry Pi case you choose is not sufficiently ventilated, you may need to make adjustments to the airflow. Some online manufacturers have started selling heatsinks for the Raspberry Pi processor — recommended if you want to run at clock speeds above 900MHz.

Juicy raspberry pi!

There are a few things you will need to take into account. Not all Raspberry Pis are built the same, so while you may hear of one person running them at a certain clock speed, it doesn’t mean your device will be able to match it.