If you have been looking at cases for your shiny new Raspberry Pi 4, I am positive you have come across ones that either include heatsinks, a fan, or both. The question is, is that just a needless extra cost, or does it really help?
Well I ended up buying a case that came with both, and decided to test if it was worth running the fan or just keeping it off.
Methodology
Now as this was my own hardware, I wasn’t about to undo stress onto it. I decided to arbitrarily run the stress tests for two minutes each, which actually turned out to be pretty good to allow the core to heat up and even out.
I would then wait for the temperature to return to idle before attempting another run. This was all run in a 26.5*C room. I followed this guide to run the programs stress and cpuburn.
No Fan, No Heatsinks
| Open air | Enclosed | |
| idle | 52 | 54 |
| stress | 78 | |
| cpuburn |
So by itself, as long as the raspberry pi is in the open air, it seemed to just hang in there for the stress test before hitting the 80*C thermal limit. Which, when hit, the raspberry pi will automatically start throttling the speed of the processor to cool it.
No Fan, Heatsinks
| Open air | Enclosed | |
| idle | 52 | 54 |
| stress | 75 | |
| cpuburn |
We can see that the heatsink helped out minimally when in the open air, but it couldn’t keep up in an enclosed case without moving air.
Fan, No Heatsinks
| Enclosed | |
| idle | 48 |
| stress | 64 |
| cpuburn | 70 |
Now that’s a difference! That tiny little fan really does do more than I expected it too.
Fan and Heatsinks
| Enclosed | |
| idle | 44 |
| stress | 60 |
| cpuburn | 66 |
Well-well-well, looky there. Putting everything together really does make a difference.
Conclusion and Chart
Lets make this a little more digestible with a chart.
It’s pretty obvious that yes, both fans and heatsinks help. However, if you have to chose just one, pick the fan any day.