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The Raspberry Pi 4 needs a fan

jeffgeerling.com

41–50 of 293 posts

Re: The Raspberry Pi 4 needs a fan

#43
post #29

> If you run computing hardware at its thermal capacity for long periods of time, this will cause more wear on the parts than if they are run well inside their limits. So I have a moderately increased likelihood of, at some indefinite point in the future, having to spend a whole $35 to replace the Raspberry Pi. I can prevent this by spending extra money (and time) up front. In some cases, it might be worth it. Maybe…

> If you run computing hardware at its thermal capacity for long periods of time, this will cause more wear on the parts than if they are run well inside their limits. How true is this actually? Personal anecdote is an I5-2500K overclocked to 4.6ghz with budget aftermarket cooler (its at 4.6ghz constantly regardless of load). It's been running 24/7 in my desktop since 2011. When will it fail? I see these disclaimers…

I've been running a I7-6700K on a 120mm AIO radiator for three years. It gets loud, but it also smashes my OC results.

Personally, my biggest worry is the pump failing, and not the fans.

Re: The Raspberry Pi 4 needs a fan

#44
Quote:

  the metal casing helps
  spread that heat around
It does, to a degree. But that is absolutely not what we are seeing in that IR picture. Shiny bare metal is a mirror at the wavelengths that thermal camera uses. So what you see on thermal image where wifi-module shield and CPU are is reflection of ambient (room) where this picture was taken. Try waving your hand around, you'll see it reflecting there too.

To measure real metal surface temperature by IR, you have to paint that metal (ideally, with black matte paint), or apply similarly-textured sticker.

Re: The Raspberry Pi 4 needs a fan

#45
post #27

Earlier quoted context omitted.

Yeah, thermal insulation behaves in much the same way as electrical insulation. If you put a conductor in series with a resistor, the conductor doesn't conduct all that well.

Seems like the winning solution would be to do as Apple does and make the case the heatsink. Aluminum is a pretty good thermal conductor, and at the very least it'd get you lots of surface area.

Like this one? https://smile.amazon.com/Vilros-Raspberry-Model-Aluminum-Coo...

(I'm just running Hassio, so can't really speak to its thermal effectiveness myself. But it's got enough weight to keep cables from pulling it off my shelf.)

Re: The Raspberry Pi 4 needs a fan

#46

I'd guess that heatsink and a case with heatpipes would be sufficient for most, though perhaps not all, uses and silent, which for me is pretty important on a Raspberry Pi

I tried a heatsink but it didn't really help unless I had a desk fan providing some air flow.

This pretty much lines up with my findings. I popped the pre-installed heat-spreader off and applied a heatsink with noctua thermal paste... basically no difference- step-by-step chaos here: https://twitter.com/Gadgetoid/status/1151442153584910337

Just adding a small fan (trying to avoid blowing our own trumpet too much here) absolutely demolishes the cooling performance of any reasonably-sized heatsink. Presumably there's just not that much passive airflow over something an inch square, even with convection.

I still wonder what would happen if a full desktop-sized heatsink was coupled to the Pi 4's SOC.

Re: The Raspberry Pi 4 needs a fan

#47

I'd guess that heatsink and a case with heatpipes would be sufficient for most, though perhaps not all, uses and silent, which for me is pretty important on a Raspberry Pi

That's what Apple used to do with their Macbooks. Heat pipes into the metal frame which conducts it over a larger surface area creating natural convections which carry the heat into the air. The real downside is that mass plays a substantial role. Meaning thicker metal, larger cases, are better than thinner/smaller. Whereas a fan can accomplish similar results for less cost and space (but not passively). If people do…

Apple has a pretty long history of passively cooled devices, including the G4 cube, which had a massive (for the time) CPU and GPU, if you wanted in it, was 8 inches cubed in volume, and cooled convectively.

Re: The Raspberry Pi 4 needs a fan

#48
post #13

Earlier quoted context omitted.

Indeed, the fan shim is insanely cool and I just bought one of these the moment that it was back in stock together with my Raspberry Pi 4. It also works on the Pi 3 and 2. Here's the link if anyone's interested: https://shop.pimoroni.com/products/fan-shim

Glad you like it! We think it's the best solution for cooling any model of Raspberry Pi that's available.

Insanely cool! Very convenient form factor too. You're about to sell two more of em.

Re: The Raspberry Pi 4 needs a fan

#49
post #29

> If you run computing hardware at its thermal capacity for long periods of time, this will cause more wear on the parts than if they are run well inside their limits. So I have a moderately increased likelihood of, at some indefinite point in the future, having to spend a whole $35 to replace the Raspberry Pi. I can prevent this by spending extra money (and time) up front. In some cases, it might be worth it. Maybe…

> If you run computing hardware at its thermal capacity for long periods of time, this will cause more wear on the parts than if they are run well inside their limits. How true is this actually? Personal anecdote is an I5-2500K overclocked to 4.6ghz with budget aftermarket cooler (its at 4.6ghz constantly regardless of load). It's been running 24/7 in my desktop since 2011. When will it fail? I see these disclaimers…

Generally the time under load is the factor that kills parts, not just time on in general. For example: components that are constantly used for test benches to run benchmarks that pin them to 100% performance constantly will burn out much faster than your case.

Also, CPUs can get "binned" where you get the best CPUs in a batch which usually result in increased longevity and higher ceilings on overclocking. People usually call this the "Silicon Lottery". You may have just gotten lucky in your case and won the Silicon Lottery. That's honestly an impressive overclock for that CPU.

I've personally never had a component burn out before I want to upgrade it either, so I'd take that common "disclaimer" with a grain of salt. I think it really comes down to if you got a good bin or a bad bin part with any component.

Re: The Raspberry Pi 4 needs a fan

#50
post #6

So does the pi 3 if you stick it in a case, even with a heatsink. I was using a pi 3 with a heatsink in the official case to play a h265 movie (which will be software decoded on a pi3). After about 10 minutes I noticed it started dropping frames and it displayed the thermometer symbol in the top-right of the display. When I removed the top lid from the case, the temperature dropped enough for the thermometer icon to…

Over the years I've used Raspberry Pis as little media players, but they kept burning out every 3-4 months; the card reader (their SSD) wouldn't work, or they'd just blink some other error message. I thought they were just cheaply made ($35 after all). Anyway, long story short, I got a fan and the last one has been working for over a year without issues.
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