Raspberry Pi 4 buy or not

Hardware
1

Hi Guys
I want to buy a new Raspberry Pi and wonder if it is worth buying the new RPi 4or stick to the raspberry Pi 3b ?

Thanks

2

Seems to be some issues with heat, so a lot of people think it needs fans.
If that makes a difference to you stick with the 3b for now

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3

I read something that it has some issue with newer power cables. It might be released a new version. I would suggest you to wait.

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4

Wait for the next version. Problems should be ironed out by then.

Either way heat will definitely be a problem if you install it in a small case. Passive cooling will be a minimum requirement.

Early adopters are starting to see the shortfalls now. Power supply issues. No booting from USB and thermal issues.

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5

I haven’t had any power supply issues with mine, but definitely a heat issue with the official case.

I has looking at the CPU usage and it was all over the place at idle. Then I brought in the CPU temp and saw it was idling at 81+ which was resulting in throttling. Popped the lid off and it now idles at 64c. Took the bottom off and it idles at 60c. CPU idles at about 3%

If I open up the front end with 3 live view rtsp cameras on it the CPU use goes up to about 15%

If I was buying new I would still get the Pi 4. Personally I wouldn’t buy a new 3. If it was a case of to upgrade an existing pi 3 I would say not to worry.

Edit: booting from SD card is a bummer, but I have mine setup to initial boot from SD, then run from a USB SSD

6

Pi4 get very very hot

I would going down the line of a real PC you will be a much happy camper.

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7

Thanks guys for your replies .
I do have a 3D Printer and some spare fans that I can create a good air flow to cool it Pi4 down. So power & cooling should not pose a big problem.
The question is to get Hassio to run from USD SSD which I think will have a better performance than the Pi3b ?

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At the moment USB boot isn’t available for the PI 4 (its coming later via firmware update). There are ways around, but if you want the HASSOS plug and play experience… we are some time off that. I’d wait until that is released - there may well be a hardware revision in the interim, if not… the getting hot thing isn’t the end of the world, you just need a fan.

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9

Pi4 without a fan will run hot

A real PC, I assume you mean x86 CPU? without a fan will run hot

Add a fan and it will run cool

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10

Mine ran very hot when I first got it, I ended up with one of these

Quality was below par, the heatspreader contact plates don’t even line up with properly with the cpu and memory chip; the CPU probably only touches about 60% of it. It does a good enough job though and reduce temps from 65C idle, to 46C.

Power supply issue wasn’t an issue for me as I kept my RPi3 PSU and used a Micro to USBC adapter. No USB boot was annoying but I just wrote my boot partition to an SD card and used that to boot the SSD.

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11

Thanks guys , I think I wait for the release of Hassio that can run on Pi4 and then get it. I have my HA running on Pi3b at the moment and so I think I wait for the new version of HA.

Thanks for your time guys.

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Good idea, really if you have a working setup it’s best not to rush into new hardware unless you really have a need for it!

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13

Yes, it is a good device, just do it.
There are significant improvements that bring a whole new level of performance previously not available on a Raspberry Pi:

  • Network is no longer connected to the SOC via USB instead it now uses a dedicated link enabling full gigabit ethernet speeds, I’ve seen 920-930Mbps using iperf as a benchmark, this is right where gigabit should be.
  • USB is no longer connected to the SOC via USB it is now connected via a PCIe bus again enabling drastic performance increase, using a USB to M2 SATA adaptor I have seen 360+MB/s from a Sandisk 128GB M2 SATA disk (note this disk is not NVMe).
  • SD card read speeds are also improved, I’ve seen 45MB/s, Pi 2/3 could only manage 20-25MB/s.

Power can be an issue however it is more related to the quality of the cable you use than the power supply itself (this has always been the case, people just seem to focus on the power supply/charger). A 1.5-2Amp supply will provide more than enough current but if you use a shitty cable it will have significant resistance causing voltage drop at the other end of the cable. I monitored power and voltage during testing and noticed that I was still getting low voltage warnings that trigger at 4.65v even though the power supply I was using was outputing a pretty stable 5.08v, I thought the cable was half decent but went and found a 3Amp rated 25cm cable at a local office supplies shop and the low voltage warnings stopped.

Heat is not really the issue, it operates below its thermal thresholds, the issue is sustained load causes the temperature to rise and eventually exceeds the thermal throttle point which is above 80 degrees. I did some testing around this and posted my results to reddit, I don’t personally think running without a heatsink/fan for light workloads like Home Assistant is going to cause it to thermal throttle, however it may if the Pi is in a case that blocks all air flow. Using a small stick on heat sink will keep temperatures low and give a decently long time at full load before thermal throttling occurs, I personally don’t like the idea of just relying on a fan. In saying this even if it does get to the thermal throttling point you probably aren’t going to notice it in use cases like Home Assistant and its not going to damage the Pi, thats the whole point of thermal throttling to prevent the SoC from damaging itself. From my testing this type of heatsink performed well without being obnoxiously large and never reached the thermal throttle point and is what I’ve now left on the Pi 4.

USB boot will be nice so if you need to wait for anything thats the one to wait for otherwise just get one.

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