Amd GPU with Ubuntu
Hello guys!

I have a PC with two AMD Radeon r9 290x GPUs.
I want to use Hashcat on Ubuntu.
My problem is as it follows:
"AMD users on Linux require "AMDGPU-Pro Driver" (16.40 or later)"
This is only available on Ubuntu 16.04
On the other hand Ubuntu 16.04 does not support fglrx (Catalyst) drivers.
As far as I understand, both fglrx and amdgpu-pro are required for Hashcat to work.
I installed it with both Ubuntu 14.04 and 16.04 and the result was the same:
"Outdated or broken AMD driver detected!"
At this point I'm stuck, I could really use some professional help.
No, there are not 2 different drivers/software that you need to install.

You might need to clean up your system first and after that install the currently suggested driver:
1. Follow:
2. download the currently suggested driver: 16.40 *

* the suggested catalyst driver version (and therefore the link) might change in the future. If in doubt, you need to check for the currently suggested driver versions

Note: for #1 it should be clear that you shouldn't have any drivers installed (e.g. fglrx related) via a package manager (like apt) like mentioned in the FAQ: "If you installed the driver via a package manager (Linux), then you need to remove these packages too"
Thank You very much!
It indeed solved my problem, guess I was confusing the many available AMD driver packages (radeon, fglrx, etc..), and thought that AMDGPU-PRO required other packages to be installed, before use...