Is this the most efficient cooling for Raspberry Pi 4?

It turns out that the ICE Cooling Tower – impressive heating for your favourite maker’s board: Raspberry Pi 4 isn’t the only efficient cooling solution from 52pi. For anyone hungry, the ultimate cooling performance without extreme dimensions 52pi has another option. EP-0163 is an ICE Cooling Tower (Amazon) that looks like something just stepped on it and made it completely flat. Is it as good as the original one?
Let’s investigate!

Ultra Thin Ice Tower Cooler

Despite the somehow ridiculous size, there are cases that can accommodate for this extreme design. Not so long ago, I covered 52pi Mini PC Tower cases which come with ICE Cooling Tower as standard and support for M.2 SSD or UPS.

The “ultra-thin” holds up only in regard to ICE cooling towers offered by 52pi. Designed in horizontal orientation, Ultra Thin Ice Tower Cooler aims to lower the side profile of the heatsink and fan combo. The heatsink actually makes contact with all prominent ICs on the PCB. It transfers heat from the CPU, as well as from RAM, USB and Ethernet IC to keep all components cool! You will find thermal pads included in the packaging.

Anyone worried about access to the GPIO header or PoE can sleep peacefully, these pins are exposed, however, access to the camera ribbon port is obstructed. It’s possible to route out the ribbon but it’s not an easy task. For obvious reasons, you won’t be able to mount any Raspberry Pi HATs unless you are willing to extend the header and invest in matching standoffs.

PWM without LEDs

This time around, you won’t find RGB LEDs embedded into the fan. They are gone, but the PWM signal is used to drive the RPMs of the fan. It’s great as previously, this wasn’t an option. From the included script, it looks like a proper implementation as well. This will come in handy if you like your Raspberry Pi 4 board working hard but without making excessive noise.

The pinout is extremely simple and follows the schema:

import RPi.GPIO as GPIO
import time
import subprocess as sp


# initializing GPIO, setting mode to BOARD.
# Default pin of fan is physical pin 8, GPIO14
Fan = 8
GPIO.setmode(GPIO.BOARD)
GPIO.setup(Fan, GPIO.OUT)

p = GPIO.PWM(Fan, 50)
p.start(0)

try:
    while True:
        temp = sp.getoutput("vcgencmd measure_temp|egrep -o '[0-9]*\.[0-9]*'")
        # print(temp)
        if float(temp) < 48.0:
            p.ChangeDutyCycle(0)
        elif float(temp) > 48.0 and float(temp) < 60.0:
            p.ChangeDutyCycle(100)
            time.sleep(0.1)
        elif float(temp) > 60.0:
            p.ChangeDutyCycle(100)
            time.sleep(0.1)

except KeyboardInterrupt:
    pass
p.stop()
GPIO.cleanup()

Thanks to this configuration you can either use the Python3 script provided or take advantage of the built-in fan utility into the raspi-config tool.

Cooling

PWM is there for a reason – at full speed, the fan isn’t noisy but definitely noticeable especially if you turn it off to compare the difference in sound levels. I suggest ramping it up to 100% only when temperatures are nearing 70℃. With a generous heatsink, this should only happen if you drive the Raspberry Pi 4 like crazy at high overclock or high ambient temperatures.

If you don’t mind a slight noise, Ultra Thin Ice Tower Cooler kept the Raspberry Pi 4 (8GB RAM version) at a chilling 32℃! That’s impressive as the ambient temperature was 24.3℃! The fan was spinning freely and the board was not burdened by any CPU-intensive tasks.

The Raspberry Pi 4 tested in the same conditions idled out at 52℃ and thermally throttled the CPU after about 5 min of running the benchmark hitting the ceiling of 82℃. You definitely want a heatsink on that CPU if your development board works hard.

Running my specially tailored NodeRED benchmark test for 20 min revealed the true performance of the fan. During my benchmark, the temperature peaked at 52℃ which is really good considering the high ambient environment. The fan which actively pushes the cold air down the heatsink cools down the contact plate too at the same time. It’s an advantage that the previous design doesn’t have. Note that the heating dissipation also applies in this case to RAM, USB and Ethernet IC which contribute to thermal saturation of the heatsink.

The original ICE Cooling Tower had the best results keeping the board at 32℃ in the idle conditions and not letting the temperature go over 45℃ during my benchmark. It’s an insanely powerful cooling solution if you don’t mind the size and remember that ICE Cooling Tower cools down only the CPU die.

Final thoughts

If you don’t care for the flair of the original design, RGB LED’s which you can mod to your liking, but looking for ultimate cooling performance – Ultra Thin Ice Tower Cooler by 52pi is the one to go for – as long as your case can provide the access for it. It’s powerful, reasonably quiet and PWM controlled – what not to like? It’s not the cheapest cooling solution, but considering its performance of it, it’s $15.99 well spent. Let me know in this Reddit thread.

🆓📈💵 – See the transparency note for details.