Redhat and Ubuntu have paid to have 64 bit versions certificate in UEFI bios. A free software group called Hispalinux has filed a complaint against Microsoft to the European Commission on the grounds that UEFI secure boot prevents computer users from installing their own choice of OS. CSM (Compatability Support Module) is legacy GPT boot.  MBR Booting is long gone which prevents DOS and Linux FAT32 booting. This also prevents USB Flash Drive booting DOS/LINUX while in secure boot mode.

Other Distributions that did not pay to play will not boot  let alone install ELAM will prevent this.  Its windows only forever once UEFI becomes Version CLASS3 with all other OS locked out.

I have the M6800 with the FirePro card.  If you have that setup, don't expect to use the AMD driver for the FirePro.  I have yet to get anything but the opensource driver to work and that means a less than preferred experience with the graphics output.  Everything is functional, but AMD should supply a driver for the FirePro.

I read a post over at AMD forum where someone managed to get the AMD package for Radeon to work (recognized the FirePro as Radeon HD 8950 w/ FirePro features), but then he had other problems.

I have a Dell M6800 with a Radeon card in it and am running Fedora 22.

Recently, the graphics started locking up.

I put Windows back on (swapped back the original disk) and Windows seems to work fine.

Has anyone seen this problem?

DX9 and DX10 based cards are End of life End of support for both AMD and NVIDIA.

NVIDIA officially drops support in april.  AMD Dropped support for these several years ago.  The Latest and Greatest drivers DO NOT WORK AT ALL for these Legacy cards from 10 years ago or more.

Just an FYI, AMD driver support for linux has always been flaky. The Xorg driver seems to work much more stable, however, you lose some of the higher functionality when doing so.

As  for UEFI, just google opensuse uefi usb install; lot's of info on how to get it done.

The original question is about compatibility; It's usually safe to say, if another linux distro works with it, any can. You may have to do some tinkering, but they all pretty much use the same code to run;

That seems to be the kind of conspiracy thinking that ends up stating there was no conspiracy after all. Anyway. CentOS 8 installed in UEFI yesterday. Flawless. Glad I had not read this poest reply. It might have messed up my setup