The Raspberry Pi 4 needs a fan

Post by bjoli » Thu, Jul 18, 2019, 7:42 AM UTC

kekepepe wrote: post #243

bjoli wrote: post #97

Earlier quoted context omitted.

That has been tried to great success with the rpi3, so I suspect it will at least make it less prone to throttling. Edit: I just stacked a bunch of 10sec coins on the processor (without any thermal compound) brought the idle temperature down by 3 degrees C. Edit2: Put an carbon tablet pipe on it, filled with coins. It is not up to heat yet, but right now it is idling at about 45C. It would probably be better with som…

What is 'carbon tablet pipe'? I tried to google it, but nothing useful turns up.

Post by rowanG077 » Thu, Jul 18, 2019, 8:46 AM UTC

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…

Post by acqq » Thu, Jul 18, 2019, 9:39 AM UTC

arpa wrote: post #254

tagrun wrote: post #249

Earlier quoted context omitted.

Let me try again. Assistant Professor of Physics here (not a grad student). Yes, reflectance of room temperature aluminum at those wavelengths is pretty good (not true for all metals BTW). Yes, this usually makes it hard to distinguish thermal radiation and reflected radiation with metals. What are you trying to say though? That whatever comes off from a metal must always be a reflection coming from somewhere else? >…

Genuinely curious person here. What is the key reason to use photon size instead of wavelenght? To stress the quantifiableness of the radiation being capured by the thermal camera? To be honest it is the first time i've seen photon size semicasually mentioned in a conversation. Then again i only had physics in high school.

Post by gadgetoid » Thu, Jul 18, 2019, 9:54 AM UTC

FullyFunctional wrote: post #201

gadgetoid wrote: post #46

Earlier quoted context omitted.

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 t…

I appreciate you actually trying. A "negative" result is still valuable. What I don't like about the article is that small fan have to spin fast (= noise) to generate enough flow. I'd much rather use a 80 mm fan, slowed way down, but I suppose I'd had to roll my own case for that. Better still, wait for someone to start offering this (or maybe this: http://blog.flirc.tv/index.php/2019/06/24/new-pi-4-cases/ )

Post by dangus » Thu, Jul 18, 2019, 10:29 AM UTC

the_pwner224 wrote: post #229

throw20102010 wrote: post #205

Earlier quoted context omitted.

It might be misleading, but it's not uncommon. Apple MacBook Pros have thermal throttled at high loads for the past several years. It has throttled for so long that reviewers were surprised that the latest version seems to be using a decent thermal paste and throttles much less. So if Apple got away with it for years on computers that mostly sold for over $2k, then I think the RPi foundation will probably get away wi…

If Apple can get away with it then the RPi will also get away with it, but it is still a highly deceptive and fraudulent practice. I spent $2000 on a XPS 15 and peripherals two years ago; if I had known about the thermal throttling I would not have purchased it. Dell literally robbed me of a thousand dollars - had I known that all the 'ultrabook'-style laptops had throttling issues, I would have bought a cheaper and…