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Just bought my raspeberry pi. BUT I NEED SOME HELP.



  • After some research, market check and taking some people’s advices i decided to buy the raspberry pi 3 B+, this RasPi charges with a 5V 2.5A microusb charger. The thing is that i ordered the wrong charger, the 5V 3A Usb-c charger for raspberry pi 4, and now due to coronavirus i can’t return the charger. Is there any problem for me to just use this charger with an adapter from USB C to MicroUSB?

    Another unrelated question, my RasPi came without the OS installed, so I proceeded to download raspberry pi imager on my computer and installed the os inside an sd card, my question is, I have to turn on the raspberry pi with the sd card inserted, and then boot up, afterwards can i erase the os from the sd carD?


  • Module Developer

    @DiogoSekeira The spec for USB-C requires a variable power output. That being said, I don’t think the Pi 4 uses that spec, and they then cheat. I wouldn’t use it, personally.

    As for the card, No. The SD Card is your drive, and will be required to boot.

    EDIT: The default power seems to be 5V, which is the usual USB spec, so a converter could do the trick, and provide plenty of power for the 3 B+ –



  • no problem at all using the pi4 power supply. the key is the 5v… the extra A will just allow you to power more things that are connected to your pi. If you connected a higher voltage it would burn out your pi.

    In my mind I liken the voltage to water pressure in a pipe… it needs to be constant, if the pressure goes up in a pipe, you can blow the fittings. Or if it’s too low, the water won’t get to the end of the pipe so it can be used.

    The amperage is like the water available that can maintain the pressure in the pipe. So if I put a lot of tubes connected to my pipe, I need a lot of water to keep all those tubes and my main pipe filled up.

    Silly way to think of it, but that’s how my Da explained it to me while he was doing some plumbing.



  • re the sd card,

    nope… the sd card is your “hard drive” without it, there is nothing for the operating system to live on, it has to remain inside your pi at all times to run the pi. The operating system has to be on it too.

    nice thing… you can have several sd cards which have different setups (different OS and/or diff software) and simply power down, switch the sd card, then power up to completely switch what you are doing with your pi. Once you get your pi setup like you want, copy the sd card by making an image or by literally copying it to another sd card, and you have insurance against an sd card failure or disaster which ruins your pi.



  • @DiogoSekeira said in Just bought my raspeberry pi. BUT I NEED SOME HELP.:

    and then boot up, afterwards can i erase the os from the sd carD?
    @kayakbabe @BKeyport
    Ok thank you very much for all your awnsers, I’m just new to this whole world and I feel there’s an infinite amount of knowledge in this field that I want to acquire.



  • @DiogoSekeira
    me too! I’m always learning. I think this is a great first project.
    Also check out the projects on raspberrypi.org . I learned a lot about python an other languages by doing projects on there.
    This magic mirror project is really neat becuase it will also help you do javascript development. If you are a web developer this is an incredibly fun way to learn more about what is possible to do on a website.

    Basically the magic mirror is a website running javascript with some special added stuff to allow us to control our computer directly so we can do things like turn on / off our monitor, get data from sensors connected directly to the computer running the website and all sorts of fun things.

    As we say in the United States, welcome to the rabbit hole!



  • @kayakbabe thank you very much, I find this community very helpful.


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