Hello

I have an Acer Aspire 515-55 with UEFI bios and I get a blank screen after trying to boot with the desktop version of 64 bits Ubuntu 18.04.4 LTS image of a USB stick. I downloaded this ISO image from http://old-releases.ubuntu.com/releases/18.04.4/

I need to install Ubuntu 18.04.4 LTS because I need to use a hardware-software and the manufacturer of this mentioned explicitly Ubuntu 18.04.4 LTS as compatible operating system but did not mention anything about more modern versions of Ubuntu.

Some tests I remember that I have already done:
- I have tried to boot with the same USB stick with an image of the 64 bits Ubuntu 20.04.2.0 LTS and this one works as expected.
- I have tried to boot with the same USB stick with 64 bits LXLE Ubuntu 18.04.3 and I get the same blank screen after selecting the install or the try live option.
- I have also tried with 32 bits LXLE Ubuntu 18.04.3 and I get the same blank screen. Nonetheless taking this USB stick to an old 32 bits computer worked alright. This leads me to think the problem might have something to do with UEFI.
- I have tried to create all these images with several apps such as: unebootin, mkusb, rufus and may be others I do not remember now.
- I have tried replacing quiet splash with nomodeset by typing e on the menu before selecting the install option.
- I have disabled the bios secure boot
- I have replaced the Optane without RAID with AHCI
- I have tried to replaced UEFI with Legacy but UEFI is greyed out in my bios, regardless of whether there is a supervisor or user password set or not.

The only thing I can think of now that I must still try is typying ctrl+c when I see the option to install Ubuntu in order to go to the Grub2 command prompt and once there trying to boot Ubuntu iso image of the USB drive. I do not know though how to boot Ubuntu from the GRUB2 command prompt.

If anyone knows or has any idea to approach this issue, I would appreciate any idea.

I already posted this question on https://askubuntu.com/questions/1319...tu-from-usb-dr but that did not help me much so far. I hope I did not break any forum rule posting a question about the same issue in this forum. I just did so because I need to be able to install Ubuntu 18.04.4 LTS asap for work reasons.

Thanks