The folks at
have dropped a new stocking-filler just in time for December that will keep your Raspberry Pi as cool as the weather outside the window.
The new Raspberry Pi 4 Case Fan costs just $5 and clips inside the lid of the official Pi 4 case.
It works by drawing air in over the USB and Ethernet connectors, which then passes over a small finned heatsink attached to the processor before being expelled through the case’s SD card slot.
This allows the
to run at full speed for longer without being throttled by the board’s built-in “sprint and recover” mechanism.
Raspberry Pi co-founder Eben Upton offers a more comprehensive explanation of the science behind the system, writing in a blog post: “Like all electronic products, Raspberry Pi generates waste heat as it works. Along with most fanless products – like most mobile phones – Raspberry Pi 4 was originally designed to operate in a “sprint-and-recover” mode: if run at maximum performance for an extended period it would heat up, and eventually throttle back to limit its temperature.”
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Upton explains that, without a case, the Raspberry Pi 4 can generally perform quad-core compiles of the Linux kernel without exceeding temperatures of 70 degrees centigrade, before hitting the throttle point. “In practice, the power optimization work that we’ve done over the last eighteen months has largely eliminated throttling for an uncased board, operating at the stock clock frequency of 1.5GHz, and in a typical ambient temperature,” Upton explained.
Stick the board inside the case, overclock the CPU or use it at a higher ambient temperature, however, and the Pi 4 board can hit temperatures of over 80 degrees. Once it hits the throttle point, the board slows down and takes slightly longer to complete the compile job, due to the higher temperature. “All of these things can put us back in sprint-and-recover mode,” Upton said.
With the new Raspberry Pi 4 Case Fan attached, the board remains well below 70C, while the compile job takes the same amount of time as on the uncased board. As a result, users can keep their Raspberry Pi 4 at a comfortable operating temperature even while under heavy load.
Raspberry Pi is promising to give some backstory to the design of its Raspberry Pi 4 Case Fan – which apparently draws some inspiration from Chinese food takeout boxes – later this week. We’re as intrigued as you are.
In the meantime, you can pick up the company’s latest piece of kit from approved Raspberry Pi resellers, listed here. Also be sure to check out TechRepublic’s dedicated
for help with your holiday shopping inspiration.