Are you running workloads so heavy that you need a lump of metal and 2 fans on a Raspberry Pi Zero heatsink? If you are, you probably shouldn’t be but hey, I’m not here to judge you. Perhaps you’re just in a warm climate? Sure, let’s go with that.
Note: This heatsink was provided by SpotPear Electronics for review. They have had no editorial input and all words are my own. They do stock a wide range of Raspberry Pi-related accessories though so do check them out on AliExpress if you’re interested.
With that out of the way, let’s get to the nitty gritty.
Table of Contents
Initial Thoughts
The first thing I notice when opening the bag is that there is no backplate for this particular Raspberry Pi Zero heatsink and I’m going to put it out there that that turned out to be a good thing in a weird way.
That weird way is that it means that the heatsink is actually compatible with the MangoPi MQ Pro and BananaPi M2 Zero as both of these boards have chips on the back that may interfere depending on how soft the thermal pads may be. The BananaPi has its own weird caveat though and we’ll get to that later.
Do note that the only contact for heat transfer on this particular heatsink is on the SoC itself. This will be fine in most cases and didn’t seem to hinder things too much, especially on the Raspberry Pi units where everything is contained in that one package. On the MQ Pro, the RAM on the underside would not be cooled.
What’s in the box?
If you grab one for yourself, you’re going to find a decently hefty single-piece “aluminium” heatsink for a Raspberry Pi with 4 (or 6 depending on how you look at it) thick fins and holes for 2 24mm fans. The 2 that shipped with my unit are GUNCAIZHU branded and state that they are 5V DC brushless with hydraulic bearings. Make of that what you will.
Other than that, you get a small square thermal pad to fit the contact spot on the heatsink and SoC, and the necessary screws to keep everything together. The 4 shorter ones hold your board in place and the 8 longer ones are for the fans. If you’re lucky like me, you’ll get 9 screws but I promise I haven’t let that extra screw sway my thoughts in any way. I’m a professional amateur.
Going back to the fan though, this is how they sounded immediately after powering on. It wasn’t pleasant but after an hour or so and some persuasion (a hard poke) they did quieten down.
Assembly
There’s not much to the assembly of this Raspberry Pi Zero heatsink really. You have the 4 screws that hold the board in place and create the pressure required to transfer heat but please do be warned that I noticed quite heavy bowing of the PCB when I screwed them in as far as they could go on the Raspberry Pi Zero 2. Easing off a little prevented this and didn’t seem to impact performance in any meaningful way. The 2 fans are wired together and connect to the 5V and GND GPIO pins (you may want to double-check the layout for your board before jamming them in!)
Moving on to the BananaPi M2 Zero issue that I alluded to earlier though, unfortunately, it’s not quite as straightforward as the Raspberry and Mango Pi equivalents.
Whilst on the Pi Zero W/2 and MQ Pro you can mount it just fine and have the GPIO headers available, on the BPI-M2 Zero the Allwinner H3 chip is further across the board. Bummer. The “good” news though is that if you simply turn the heatsink around, it then lines up and cools it. The bad news is that you then lose access to GPIO pins and thus your ability to power the 2 fans but in all fairness, SpotPear doesn’t market this as a BananaPi heatsink so this pickiness is my own fault.
Raspberry Pi Zero Heatsink Test Results
Just the one graph for you today and as you can see, there’s a gap where the fan-related results should be for the BananaPi M2 Zero. This isn’t their fault, I’m just including them because I can.
Testing consisted of 2 separate runs. One with the heatsink and 2 fans and another with just the heatsink on its own. SpotPear does offer a fanless Raspberry Pi Zero heatsink option so I thought it would be worthwhile to compare this if you’d like to save a little money there. stress-ng was the load tester of choice.
I did these measurements over a couple of days and as such, the ambient temperature fluctuated from 24 degrees celsius to 25.8 in the varying tests. I standardised the data as if it was 24 degrees celsius to keep things a little fairer.
The results should be of no real surprise here but it’s nice to see that it’s doing a great job. On the most power-hungry board in the lineup, the Raspberry Pi Zero 2, we see an idle temperature of 9.8c above ambient. This only increases to 22.9c above ambient under full load with the heatsink and 2 fans doing everything they can to keep things under control.
Turning the fans off saw a 5.6c increase in the Pi Zero 2’s idle temperatures and a 17.6c jump under load. This pattern rang true on the other boards too, though the lower power draw and heat output of the original Pi Zero W and the MQ Pro means the spread is a little smaller.
Does the Raspberry Pi Zero Need a Heatsink?
Not all of you reading this will need a Raspberry Pi Zero heatsink as you may not going to be pushing them too hard, or if you are, they’re likely going to handle it like a champ (shout out to the little monitoring Pi I have back at my parents’ shoved behind a cabinet running at 70c 24/7, you’re a hero).
Does the Raspberry Pi Zero need a heatsink though? Probably not in most cases but for the $5-6 that this particular model is going to set you back, I would highly recommend investing in one. The fans can be a little whiney (it actually reminded me of being back in Japan and hearing the chorus of Cicadas) but if you give them a poke they’ll soon shut up.
Saying that though, the 2 fans do draw around 0.7 watts on top of your board’s own power draw so that’s definitely something to take into consideration if you’re using solar or battery power for your boards!
Final Thoughts
Whilst it’d be lovely for me to be able to keep cool under the most stressful of conditions for $5-6, unfortunately, I can’t. Therefore I feel like I owe it to the Raspberry Pi Zeroes out there to speak on their behalf and say please do it for them. They’d do the same for you if they could.
Where can you buy one?
SpotPear Electronics sell these both on their own AliExpress store and have further information and product photos available on their website.
