How to fix screen mismatches on your Raspberry Pi

You receive your plate, you mount it, you get it to turn on normally, you enter the operating system and… what is this? What it is, is normal. Or more than normal, usual: few times we will connect the Raspberry Pi to a monitor and we will see that the interface of the operating system fits perfectly, and with this it does not matter if we use Raspbian or any other operating system. The board tries to understand what it is connected to, but it often fails to display the window correctly.

Solving it is simple, but it is not if we are used to starting an operating system and it fits perfectly or, failing that, we can solve it from a simple settings menu. The operating systems for the Raspberry Pi include a configuration file that we must edit if we want everything to be correct, although it may also be a good idea to disable a driver. Here are the two modifications you have to make so that the operating system fill the entire screen without sticking out.

Edit the file config.txt and disable the GL driver on our Raspberry Pi

Once we know what we have to do, configuring the screen of our Raspberry Pi will be a matter of two minutes. We will do it as follows:

1. We open a terminal and write the following:

sudo raspi-config

2. We go to the Advanced options section and then to GL driver.
2. We chose «Legacy». This may not be necessary. The following, yes.
3. We edit the file config.txt which is in the / boot folder of our micro SD card. We can do this in different ways: from any text editor on Linux, macOS or Windows or from the Raspberry Pi operating system. If we choose this last option, we have to open a terminal and write sudo nano /boot/config.txt, we make the modifications, save and exit.
4. With the file open, what we have to modify are the lines where it says "overscan". We have to remove the pad to activate the line (change the color to white) and test values ​​until the screen fits. We will use positive numbers if we see black bars and negative numbers if the image sticks out. We won't see anything until we restart the computer.
5. We reboot.

And this would be it. It would be nice if they included a simpler option that we could modify from a menu, but once we know it, the problem is not that serious. Now Martin Wimpress needs to launch Ubuntu MATE for the Raspberry Pi 4, add it to NOOBS and we can use a fully adapted version of Ubuntu, which I don't quite like Debian.