Any advantage in using Pi4B over Pi3B+?

Hi, I bought a Pi4B to run Octoprint but those green LED never got turned on. I returned it. Now, I can choose between Pi3B+ and Pi4B. With the bad experience I had and heat issue reported by other users, I wonder if I should buy the Pi4B rather than Pi3B+ to run Octoprint. Any advantage in using Pi4B over Pi3B+?

You may have a look on this thread:

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Thanks. How likely will future version (in 1-2 years time) of Octoprint require more powerful pi than the Pi 3B+?

As the cost of the Pi 3B+ and Pi 4 2GB is the same price (in the UK) anyway I am not sure why you would buy a 3B+ (other than that it runs cooler). I use a 3B+ as I had a spare hanging around.

It is unlikely the core functionality will need the performance of a 4, but you might choose plugins that need more power. Maybe Octoprint will go 64 bit only, but that would still work on a 3B+. So not sure that is a huge issue.

Edit: BTW was the RPI 4 you tried before a 1, 2, 4 or 8GB flavour? And where you going to use a webcam of sorts

The heat issue was fixed shortly after the Pi4 was released with a firmware update. You will see absolutely no benefit of the Pi4 over the 3 with Octoprint.
Be willing to bet the issue wasn't with the Pi4. Octopi image was released before the Pi4 and does not have the boot files required for it

I can buy a brand new Pi 3B+ at about 40% cheaper than the Pi 4. Troubleshooting and compatibility with cooling solution and the touch screen as well as the frame are the main concern here. I consider 3B+ because I tried the Pi 4B 4GB and green led did not turn on. Tried all sorts of trouble shooting and wasted 2+ days already. Also concerned about heat as I may put it behind the official pi 7" touch screen and possibly the Pimoroni Pi 7" Display Frame. I cannot find a cooling solution if I put all three products together. Getting a tall fan with heatsink may block the Display port.

Yes, I want to use a webcam. Logitech C920x or Pi Camera V2.

In that case I would just go with the 3B+. I use the FLIRC heatsink case on my Pi4s, but I don't see the 4 will give you much more than the 3B+, with the caveat that every install is slightly different combination of plugins.

So even a 3B+ can handle a 7" touch display and real-time video feeding from camera at the same time?

You can run large touch screens on some of the first Pi's, and people have had 3 Camera's running of Pi 3B+'s. So I don't see why not. I am not running any of the touchscreen plugins myself so not sure on their load.

Thanks. Could anybody who have run commonly used touchscreen plugins comment on the load?

There are some changes to the 4B which might be worth mentioning: the power connection is different, the HDMI connection is different, it needs to be cooled to be happy. So I wouldn't call it a simple replace; you need to consider the add-ons.

I find it to be fantastic in the development space where you're installing things which need to be compiled (faster). I like that I can put a fast microSD card in there, seems to speed up read/writes. I love the extra RAM.

Thanks for mentioning about the power connection. I bought a Pi4 B+ 4GB with the Official USB-C Power Supply and a case. The Pi4 is DOA. After reading some issues with the Pi4 and that the Pi 3B+ can run Octoprint equally well, I decided to go for the Pi 3B+. After hearing from you about the power connection, it seems that the Pi 3B+ does not use USB-C for charging. Am I correct? If I go for the Pi3B+ which is 40% cheaper than the Pi4, I will waste the USB-C Power Supply and the case. I cannot use the Aron case anyway because the connector to the official Pi touch screen is blocked by the case.

compiling marlin on a pi4 when using the pandapi shield would be faster.

this is the only thing i would like to have.
But how often have you really to recompile marlin ...

Pretty much any case is incompatible between different models, for example from Pi3B+ they changed power to USB-C (Was micro-USB), 2 mini HDMI ports (Was one fullsize) and swapped the ethernet & USB ports.

I have a Pi4 for my OctoPrint as the Pi3 I was using died and they were the same price. It runs cooler than the Pi3 did, but the Pi3B+ added the metal heatsink kind of thing so I believe that would be the 'coolest' pi about.

In terms of performance, if you are looking to run a touchscreen off the same Pi as OctoPrint then performance starts to matter. On startup my Pi struggles for a few seconds starting OctoPrint, desktop and chromium but give it a minute and once everything is loaded it is plenty quick enough. Both models are quad-core, but this doesn't really matter since currently OctoPrint only runs on a single core. To be honest, I don't think you'd notice much difference.

If the Pi3B+ & micro USB power supply is cheaper than Pi4, I would go for it.

Edit: If you want performance numbers, my Pi4 is idling about 20% with 2 web clients and camera streaming.

RPIs have a way of breeding, like arduinos or possibly gremlins.

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Or mechanical keyboards.

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The 3B+ and the 3A+ both have the same micro USB connection as the 3B did. There are times when I think that a dedicated/vanilla OctoPrint on a 3A+ is a good fit. Since it has a single USB connector then you can just toggle on/off the 5V power on that bus to prevent it from sinking power over to the controller board (without worrying about the other connectors). Granted, it has 512MB of RAM but the form factor is slightly smaller. I would suggest that Prusa should consider changing their default configuration to adding a female GPIO header to their board and then provide housing which will accommodate the 3A+ (rather than a Pi Zero).

Compiling numpy during its install is something that comes to mind. It's at least 20 minutes on the 3B.

I had major problems with my RPi 2, turned out to be the power supply. I bought a RPi 4 B w/ 4gb, added a case and touchscreen. It runs with the new software w/o a fan or special heatsink. My prints run to 6 hours with no issues. I haven't run any longer prints, so I don't know if a heat problem could develop with longer print times.

It is more that as the temperature of the cpu gets higher the pi will start throttling the cores back and it is easy to end up with a pi 4 that runs slower than a pi3b+. You can monitoring the cpu temp and throttling quite easy, but a lot will depend on the load and the ventilation.

For example my Pi4 that is a Plex media server uses a lot of cpu when transcoding and is in a warm place with poor ventilation, I.e. a tv cabinet, so it always throttles back without extra active or passive cooling. This results in jerky play back. In fact just using it as a desktop with the original pi 4 on used to cause it to start throttling back.

Of course it may not be an issue for you, it might it not be throttling back or it might not be causing you an issue with prints. But it is certainly worth bearing in mind when you by a Pi4.