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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

#191

Post by mindcrime »

whiskers wrote: post #75
whiskers wrote: post #37

Earlier quoted context omitted.

By default it's always on. If you (optionally) install the daemon then it can use the Pi SoC's internal temperature sensor to control dynamically based on need.

@mindcrime - I can't reply to you due to max depth. The current version doesn't, we're having a new, custom, fan made with an RPM feedback line for a future model but it'll be a couple of months yet.

... we're having a new, custom, fan made with an RPM feedback line for a future model but it'll be a couple of months yet.

That's good to know. Thanks for the update!

Re: The Raspberry Pi 4 needs a fan

#193

Post by codesushi42 »

pslam wrote: post #146

This article is actually describing how the Raspberry Pi 4 does NOT need a fan. This is not the 1990s. It is perfectly acceptable and even advantageous to design for a high peak:normal load ratio, with thermal throttling. In this case, it allows for a compact, cheap, fanless design for the vast majority of users. There is no evidence the heat dissipated will impact lifespan. It is common for the components picked out…

Fans fail too.

The heat dissipated will probably shorten the lifetime of the board. At $35 who cares though? And you have more to worry about from the SD storage.

The RPi needs an SSD. :)

Re: The Raspberry Pi 4 needs a fan

#194

Post by [deleted] »

sjustinas wrote: post #153
marcosdumay wrote: post #120

Earlier quoted context omitted.

The Pi4 is overpowered for a Kodi box. That said, there is a huge number of applications for overpowered LED blinkers, and no lack of people to use them. And there is a great deal of educational value on having those boards available and easy to get. Besides, it's becoming hard to find people without access to a machine where they can learn basic computer science. So this one niche is closing down, while the Pi is st…

Could you elaborate on why you think Pi 4 is "overpowered" for Kodi? From what I've seen, there are still some kinks playing 4K HEVC videos. So hopefully, when software/firmware/etc. catches up, it should be "just powerful enough" for a Kodi box, all because of hardware decode. Barely handling 4K does not scream "overpowered for a media center" to me.

[deleted]

Re: The Raspberry Pi 4 needs a fan

#195

Post by CliffStoll »

JorgeGT wrote: post #144
DINKDINK wrote: post #137

Earlier quoted context omitted.

>people nowadays is using IR cameras without any calibration or understanding of the physics behind the measurement The four factors are Emissivity (ε), Absorptivity (α), reflectivity (ρ) and transmissivity (t). Emissivity is only one facet. Ideal is high Emissivity and low reflectivity. https://en.wikipedia.org/wiki/Radiation_properties

Certainly, in most cameras the factors are in fact accounted for by setting the emissivity factor, a reflected apparent temperature, the distance to the object and the relative humidity. Thermography is certainly not an straightforward "point and click" process...

As a once-infrared-astronomer, I can certainly confirm your statement: Thermography is certainly not a straightforward "point-and-click" process.

Six years of grad school...

Re: The Raspberry Pi 4 needs a fan

#196

Post by jrockway »

NightlyDev wrote: post #178
blackflame7000 wrote: post #126

Earlier quoted context omitted.

Also if you are not using a good power supply the Pi will happily operate on less current except when it needs that current during power-intensive operations like watching a movie. This could be causing silent corruption as it happened in my case. If you ever see a thunderbolt symbol best check your power supply.

What are you guys using since you're talking about symbols?

It's part of the default desktop UI in Raspbian.

Re: The Raspberry Pi 4 needs a fan

#198

Post by close04 »

darkmighty wrote: post #186
JorgeGT wrote: post #116

Earlier quoted context omitted.

Yep, a lot of people nowadays is using IR cameras without any calibration or understanding of the physics behind the measurement. The truth is, the camera requires an emissivity coefficient to associate the received radiation with the emitter body temperature. There are tables for different types of materials, but the best is to calibrate against a surface thermocouple or similar. A corollary of this is, when you see…

Indeed, but note it usually works well enough, because most surfaces have high IR emissivity (in particular with organics like plastics, papers, woods, fabrics, etc.; soils and liquids as well). The one exception you have to be careful is with unpainted metal (high reflectivity). If polished it can be so low that even calibration doesn't help -- because you'd need extremely precise calibration that isn't practical an…

This is a more accurate representation of RPi 4 temps[0].

[0] https://www.raspberrypi.org/magpi/raspberry-pi-specs-benchma...

Re: The Raspberry Pi 4 needs a fan

#199

Post by Duladian »

I picked up a 2G Pi 4 yesterday and did some basic thermal testing using the onboard thermal readouts.

None modified Pi 4 running the latest Raspbian will idle at 67C in a room that is 22C.

Pointing a small 30cm 5V fan powered off the GPIO header will reduce this to ~50C.

Placing a heatsink on both the CPU and RAM reduces the temp to 50C.

Modifying a Pi 3 heatsink + fan combo to fit the Pi 4 results in a 42C idle temp.

The life expectancy of the board may be decreased due to the higher idle temp. IMO I would say a heatsink is the bare minimum for running a Pi 4 and a heatsink fan combo is required for anything process intensive such as 4k video.

Re: The Raspberry Pi 4 needs a fan

#200

Post by Florin_Andrei »

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…

I've a Pi3 with a CPU heatsink, in case. I have not seen it throttle after adding the radiator.
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