Pi4 cooling fan

Has anyone had experience of the Pimoroni Fan shim on a Pi4 running RISC OS?

Yes. They work quite well and Andrew Conroy has some software to control the fan and LED. However, in my experience, quite a proportion of them dry out after a while and make more noise than is worth bearing (pun intended!).

The FHANtom might also be worth considering, if space allows.

Yes. I have a Pi4 with the Pimoroni Fan shim, and a Pi4 with the Labists box+fan. Both excellent.

Thanks for the info. Overclocking my otherwise bog-standard Pi4 to 2000MHz raises typical operating temps here to the mid-Sixties or more, so now that the English summer threatens to actually arrive, active cooling is indicated.

I had a fanshim on one of my Linux Pi 4Bs for about a year, Pimoroni sent me 3 replacement fans free of charge, but every one went whiny as andym says. In the end I abandoned it, and got a case with a 40mm running on 3.3V. They are far better at cooling and quieter than 30mm fans, particularly the very thin one used in the fanshim.

Another alternative is the large metal heatsinks cases that cover the entire front and back which Pimoroni also sell, which I have on my RISC OS Pi 4B. That maintains a pretty steady 50C.

I do miss the LED changing colour depending on Temperature, but I’m sure Andrew Conroy can describe how to replicate on RISC OS that without the fanshim.

Another alternative is the large metal heatsinks cases that cover the entire front and back

Had one of those from Pi Hut fitted with twin fans. Temperature of Pi 4B kept between 32-36C.

Update: ordered the fanshim – done before I’d read Druck’s post :-( – but so far, so effective: avg. temp hovers between 37-47 deg with the Pi clocked at 2000MHz, and it’s virtually inaudible, so far at least, operating full-time as I’ve no temp-related fan-control software. I suspect even if there were, the fan would still be running most of the time, as without it the CPU core gets up to 70 deg – I’ve no heat-sink or passive cooling.

An aside on Pi overclocking: while the perfomance boost from overclocking the CPU is linear, raising GPU speed from 500 to 750MHz makes almost no difference either to real-world tasks or benchmarks – presumably because RO makes very little use of hardware acceleration?

If you are using the CM4 then a Waveshare 3007 fan is best – it mounts directly on the CM4 and has a solid metal heatsink. Fan control requires custom hardware and FanCon from !Store. See here (this is a set of draft instructions).

https://thepihut.com/products/tall-aluminium-heatsink-fan-for-raspberry-pi-compute-module-4-cm4

This fan doesn’t require any extra hardware. Uses CPUClock to control when the fan turns on and off.
Using the 3.3V gpio pin reduces fan noise/wear.
Keeps the temperature below 55C even at 2.4GHz. The fan only turns on for short periods.

Fanshim… it’s virtually inaudible

Yes it’s great to start with.

I have just bought a Raspberry Pi 4 and wonder whether it can be run without a fan or heatsink, if not overclocking. If not, which is better, a heatsink or fan?

I have just bought a Raspberry Pi 4 and wonder whether it can be run without a fan or heatsink, if not overclocking. If not, which is better, a heatsink or fan?

The Pi 4 can only be used without a fan or heatsink if you’re using it bare-board (with lots of ventilation). The moment you put it into a case, you’ll need some means of dispersing the heat.

Fans have already been discussed upthread, so I’ll concentrate on heatsinks.

A CPU heatsink (of the type you may have used on a Pi 3) won’t be enough for the Pi 4: you’ll need something bigger. In addition, many cases have restricted airflow (and either expect you to use a fan or haven’t thought about the problem at all). It is worth noting that the Pi 400 relies on a passive heatsink for cooling, so the airflow problem can be solved.

One way of solving the problem is to get a case that doubles as a heatsink:

• I use the FLIRC case for my Pi 4: I find that the operating temperature rarely exceeds 20 degrees above ambient (i.e. it will hit 50C on a hot day). One disadvantage of the FLIRC case is that you can’t use the GPIO pins.
• Pimoroni sell an “Aluminium Heatsink Case” that allows access to the GPIO pins. Thermal performance is on a par with the FLIRC case, but the Pi 4 circuit board isn’t fully enclosed (and any HAT you install will have to be outside the case).
• The Argon One case is another possibility. It’s a heatsink case that has a built-in fan (so would be suitable for overclockers), but as I haven’t got one I can’t comment on its performance.

The Argon One case is another possibility

The one I have keeps the temperature at around 43-46C. Apart from the Pi 4 it also contains a SSD. Not overclocked, has access to the GPIO pins.

I have just bought a Raspberry Pi 4 and wonder whether it can be run without a fan or heatsink.

It can, but (as Stuart mentions above) good ventilation is essential. I ran mine for years at standard CPU settings mounted as a bare board on a 100mm VESA mount on the back of my monitor, which also got it out of sight and potential damage. Even in summer temps didn’t exceed what I regard as a safe limit, 65-70 deg.C.

Thanks for replies. I will probably go for a fan.

UPDATE: the Pimoroni Fanshim I ordered 18 August and installed a few days later has just expired. It couldn’t be toggled on/off by CPUClock having only two wires, so had run for roughly 500 hours since installation.

I had a fanshim on one of my Linux Pi 4Bs for about a year, Pimoroni sent me 3 replacement fans free of charge, but every one went whiny

Can’t say I wasn’t warned…!

How were you running it? 5V or 3.3V?

For the 3B+ (I don’t have a 4), I got a case that came with a fan (specifically https://www.amazon.fr/gp/aw/d/B07MX5B8HH).

As I have something on the GPIO, I had to mount the fan backwards on the outside. It is wired up to 3.3V to provide gentle airflow without noise or stressing the motor. It’s been running since I fitted it at the end of 2021.

Photo: https://heyrick.eu/blog/index.php?diary=20211227

How were you running it? 5V or 3.3V?

I have no idea: I fitted it on the end six pairs of GPIO header pins (those nearest, when viewed with the pins on the lefthand side of the board) as instructed by the Pimoroni installation sheet.

In the meantime, I’ve dialled the CPU back to 1800MHz, and fitted an old ‘pronged’ heatsink which I’d had on a previous Pi. But a proper fan will be needed, I think (and thanks for the tip, Rick).

This heatsink and fan works with CPUClock and RPi 4.

When I added the fan control to CPUClock (by user request), the only fan info I had was for the ‘official’ Pi fan. Thus the GPIO pin used to control the fan was hardwired in to the software. If anyone wanted to use a different GPIO pin, then I could compile a custom version.

If there were sufficient demand, I could make the GPIO pin used user configuerable, and save it in choices.

If there were sufficient demand, I could make the GPIO pin used user configuerable, and save it in choices.

That seems like a very good idea anyway!

This heatsink* and fan works with CPUClock and RPi 4.

@ Chris Gransden: I’ve acquired one and fitted it. The fan runs full-time, despite temps not reaching the trigger speed set in CPUClock. I’ve clicked ‘Enable fan control’ and set Fan trigger temperature to 50C; do I need to add anything to Config.txt settings?

[*Pi Raspberry Pi 4 Armor Lite Heatsink with PWM Fan, Raspberry Pi Aluminum Heatsink Cooling Kit With Fan Speed Control for Raspberry Pi 4 Model B]

I’ve clicked ‘Enable fan control’ and set Fan trigger temperature to 50C; do I need to add anything to Config.txt settings?

Having just set up a pi4 I’m following this with interest. I need this to be in a case, and the case it came with has minimal ventilation.

When I added the fan control to CPUClock (by user request), the only fan info I had was for the ‘official’ Pi fan. Thus the GPIO pin used to control the fan was hardwired in to the software.

Was it Pin 14 by any chance? That’s the one used by the ArmorLite heatsink/fan I’m using. The accompanying (Linux) instructions say to open a terminal and type ‘sudo raspi-config’, which makes me think the bootloader’s Config file needs an additional line inserted. Something like ‘P4 Fan=Yes’, but I don’t know the correct syntax.

Was it Pin 14 by any chance?

It is pin 14. I have no idea whether any lines must be added to config.txt as I do not have a Pi.

Incidentally, I was just looking at the source today to see what would be needed to make the pin number configurable. It should be possible, but more than I first thought.