How to keep your Raspberry Pi 4 cool
The Raspberry Pi has seen great increases in CPU speed since 2012. From a single-core 700MHz CPU to the latest Pi 4 and a 1.5GHz quad-core CPU is quite a difference, and with this increase in power there is an inevitable increase in heat. The Raspberry Pi 4 has a rather warm CPU: a stock Pi can idle at 39°C, and under extended heavy load it can reach up to 80°C! There are now many companies offering their version of a cooling system to help prolong the life of the Pi 4 and stop our fingers getting burnt. But which is the most effective? Which is the cheapest? And do we need passive or active cooling?
Passive vs active cooling
Passive cooling is when a CPU is cooled using a heatsink or pipe, which draws away the heat from the CPU to a series of thin metals fins that are designed to offer the most surface area from which the heat can dissipate. CPUs have used heatsinks since the late 386 devices, and this was enough for most CPUs.
But with the rise of the Pentium era, extra cooling was required and this is where active cooling became the norm. With the more powerful Pentium CPUs generating more heat as their speed increased, heatsinks were no longer enough and fans were needed
