We love squeezing as much performance as we can out of our Raspberry Pi computers and since it's so easy to overclock the little guy, we all do it. We also like to protect our beloved little machine in an enclosure, which may reduce air flow around the board. One thing to keep in mind is that it is easy to exceed the thermal specifications of the SoC and Ethernet chips in these conditions. In fact, the good folks at Geektopia spent some time with a Fluke Ti35 thermal imaging camera (see second picture) studying the heat signatures of the Pi's chips during common use scenarios, such as playing HD video from a USB flash disk, streaming video over Ethernet, transferring large files over Ethernet and stress-testing the CPU as if running a compute-intensive process. For instance, streaming HD video over a wired network connection reveals that the Ethernet chip gets toasty at 65.1 degrees Celsius (149.18 degrees Fahrenheit).

While Geektopia concluded that the Raspberry Pi does a good job at dissipating heat under normal conditions at a relatively warm room temperature (26.9 degrees Celsius; 80.42 degrees Fahrenheit), in a draft-free environment and outside of a case, they also concluded that it's also very easy to reach or exceed the thermal specifications of the Pi's chips, which can lead to premature board and component failures. To help alleviate such thermal stress, it's wise to equip the Raspberry Pi with passive heat sinks such as these copper beauties designed to fit the Pi's voltage regulator, CPU / GPU and Ethernet chips. They are easy to install thanks to the included double-sided thermal tape.

These passive copper heat sinks will reduce the chips' temperatures by 4 or 5 degrees, based on empirical testing in a room where the ambient temperature was about 18 degrees Celsius (64.4 degrees Fahrenheit) with a Relative Humidity of ~44%. Of course, results will vary based on the ambient conditions of the room. If you're using a Nwazet Power Supply with your Raspberry Pi, it's also a good idea to install heat sinks on the voltage regulators as they will warm up just like the Pi's own voltage regulator.