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The Raspberry Pi 4 needs a fan

jeffgeerling.com

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Re: The Raspberry Pi 4 needs a fan

#51

Post by NikolaeVarius »

junaru wrote: post #29
adrianmonk wrote: post #22

> 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…

Last time I checked, a consumer grade CPU has expected lifespan of 20-30 years, so your CPU is still in its young adult years

Re: The Raspberry Pi 4 needs a fan

#52

Post by gadgetoid »

kees99 wrote: post #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 meas…

There's a better image here- https://medium.com/@ghalfacree/benchmarking-the-raspberry-pi...

Re: The Raspberry Pi 4 needs a fan

#54

Post by [deleted] »

spiderfarmer wrote: post #25
adrianmonk wrote: post #22

> 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…

I would accept the shorter lifespan just because of the fan noise. Small and cheap fans are very noticeable in otherwise quiet rooms. I'd hate it.

[deleted]

Re: The Raspberry Pi 4 needs a fan

#55

Post by geerlingguy »

kees99 wrote: post #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 meas…

True, I worded it a bit wrong. But the metal case is a huge improvement over the plastic die package on the Pi 3 B and earlier—a heat sink helps a little but you don't yet _need_ one if you use a fan, since the metal is much better at dispersing the heat.

Re: The Raspberry Pi 4 needs a fan

#56

Post by seanhandley »

dbg31415 wrote: post #50
LeonM wrote: 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.

SD cards have a limited number of writes so if you have the OS constantly writing to it then eventually it sets itself read-only.

You can mitigate this somewhat with https://github.com/azlux/log2ram

With some finagling you can get them to boot an OS from an external disk then your SD card can just hold a read-only boot loader.

Re: The Raspberry Pi 4 needs a fan

#58

Post by [deleted] »

kees99 wrote: post #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 meas…

[deleted]

Re: The Raspberry Pi 4 needs a fan

#59

Post by cwyers »

geerlingguy wrote: post #28
BaconJuice wrote: post #20

Just a bit off-topic but what are you guys doing that you need to do CPU throttling? I just got a Pi4 and wondering if I'm missing out on some cool projects I can do with it :)

The Pi 4 is the first generation that's actually not horrible at running Kubernetes, so I'm mostly having fun with that (ongoing saga at www.pidramble.com).

Is this just about how fast the CPU is, or is there some other reason the k8s experience is better now?

Re: The Raspberry Pi 4 needs a fan

#60

Post by nixgeek »

gadgetoid wrote: post #52
kees99 wrote: post #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 meas…

There's a better image here- https://medium.com/@ghalfacree/benchmarking-the-raspberry-pi...

How was that accomplished? Extremely nice image!
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