HDMI on Rasp PI 4 don't work

I installed a version of Raspbian on a Raspberry PI 4 and everything is ok and works very well.

I wanted to install the Ubuntu MATE 18.04.4 LTS version.
I create a new boot sd card with the right image
I boot on the image sdcard and nothing is displayed on the screen.
I tried the corrections that talk about the subject on the internet of the config.txt file

i try
nothing better

i try
or hdmi_safe=1

nothing's better!

I don't know what to change as a parameter .
Could you please help me...

Thank you


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Hi :slight_smile:
It is trying to boot ? Is the LEDs blinking when you are plugging ?
Did you gave a try to the 2nd HDMI port ?
Raspbian done a special version for Pi4 as the HW improved a lot since Pi 3 B+. I don't see mate release for Pi4 here https://ubuntu-mate.org/ports/raspberry-pi/ :

Supported Raspberry Pi

  • These images will work on:
  • These images kind of work on:
    • Raspberry Pi 3 Model A+ (not recommended)
      • Fails to complete the first boot setup due to insufficient memory.
      • If you have completed the setup on another Pi that card can be inserted in a Pi 3 Model A+ and it will work.
      • Due to only having 512MB RAM the arm64 is not recommended. The armhf version can be very tight on resources.

Unsupported Raspberry Pi

Yes, the LEDs are on and I tested both HDMI ports.

The boot to install the ubuntu-mate-18.04.2-beta1-desktop-armhf+raspi-ext4.img.xz image doesn't show anything on the screen.

The boot to install ubuntu-18.04.4-preinstalled-server-arm64+raspi3.img.xz shows the progress from the beginning of the environment check to the Login Password prompt.

So it would be impossible to install Ubuntu 18.04 desktop on a PI 4 even in 32 bits?
in which case I'm more than disappointed


It will come :slight_smile: but maybe you have to wait a while. You can use your Pi 3 B+ up to this moment.
If you have some free time and some willing to learn, you can contribute to its build for pi4 :slight_smile:
Im also waiting my side for pi4 support with retroPI.

Is the LED blinking or only power on ?

Hi Olek

The red led is lit permanently, the green one flashes 2 " times at the beginning of the boot then goes out.
So I will have to be patient, and without being able to participate in the creation of a new build, I unfortunately do not have the necessary skills.

Thank's a lot for your response :blush:

There is one guy here that found a image working on pi4 :slight_smile:
Maybe together you will make some good work that both will be happy.

Also digging i found this solution :

I've used this image without undue problems. If you don't see anything, then it is advisable to know what resolution works with your monitor/TV (with things like raspbian) so you can adjust config.txt accordingly. I've noted that hdmi-safe doesn't agree with a number of recent monitors/tvs.

Hi Derek i will try to find a solution with what little knowledge I have of linux systems.
thanks for your help !


As has been said already, there is no self-contained distribution of Ubuntu-MATE that works with the Raspberry Pi 4. However, that does not mean you cannot end up with it. Moreover, except for one and a half "blips", it's not at all difficult:

Go to the Ubuntu web site and download your choice of the 32-bit or 64-bit Ubuntu server image for the Pi 4. Write that to the SD card as you would any other image. Boot this, log in, install MATE as your desktop (from the command line, as there is no desktop present).

Except for not having the Raspberry Pi tools, you'll now have Ubuntu+MATE on your Pi (instead of Ubuntu-MATE.

Now as for the blips I cited: You'll need to connect the Pi to your network over Ethernet for the initial boot/setup, as Wi-Fi won't work (easily anyway), and you might not have video output. That will depend on whether the monitor's resolution is that of a valid mode or close to one, but readily fixed in the manner you've already done.

There are two videos on YouTube for getting this setup going. One is by "NikoD" (or something close to that) and the other by "ETAPrime". As best as I can remember, either mentions the ethernet or the video thing, but each does add additional things the other doesn't (the combination of both gives you a more complete setup). You can ignore the "cannot see all the RAM" warning from NikoD (it's been fixed since), but DO incorporate zram anyway.

Except for the lack of those Pi tools (you can add some of them manually; there are how-to guides for it online), I've found this arrangement to be much more stable.

There are links to the videos in question and more in the following thread: Is Ubuntu Mate available for the Raspberry Pi 4 yet?