How to safely uninstall Catalyst?

[Pocket]

I've given up on AMD ever porting their newer Catalyst drivers (post-13.1) to "legacy cards" like mine, so Plan B is to uninstall it and install the latest open source drivers and see if that works. The question is... how? I went through a bunch of rigmarole in the terminal to get it set up in the first place, and I have no idea how I would transition back without breaking something. I'm on Kubuntu 12.04 x64, and I couldn't even apply system updates without screwing up Catalyst so badly that I could only boot into command-line mode until I wiped and reinstalled everything.

[Letalis Sonus]

Even when installed through the graphical installer, it should detect your system and build packages for it, so you can just sweep it with apt: sudo apt-get purge fglrx*

Just don't forget to delete your xorg.conf afterwards, it might interfere with other drivers. Then you're done, no other steps are needed.

[Pocket]

Do I have to reboot into text mode or something to purge the files, or will it be able to seamlessly transition back to the right drivers?

[Letalis Sonus]

You'll need to reboot in order to let the system load the other driver once you're done, that's all.

On Linux you can pretty much delete every file currently being used, the system will keep it in memory until it is no longer needed - no matter how essential it is for the system.

[###O?qÿáÓ]

There is an uninstal script in

/usr/share/ati

If you use this, all fglrx files should be removed.

[Letalis Sonus]

However, it is only available if the driver was not installed via apt/dpkg.

[Dusk of Oolacile]

Originalmente postado por Letalis Sonus:

However, it is only available if the driver was not installed via apt/dpkg.

If it was, you remove it by apt/dpkg. Isn't it logical?

[Pocket]

So now that I'm ready to actually do this, I'm confused about what upgrading my Radeon driver actually entails. This page[help.ubuntu.com] says at the bottom of the supported cards list "Requires Ubuntu >= 12.10 or updated package". Does that apply to the driver itself or just certain cards? Which of the thousands of packages that make up my system does it expect me to update if I decide not to upgrade the whole OS to a newer release? (I'm on Kubuntu 12.04 and I'd rather wait for the next LTS release before I upgrade.) Will installing the system updates that Kubuntu has been bugging me to install, and/or running an apt-get dist-upgrade, do the trick? For that matter, would doing either of those things just update the driver for me?

[Benjamin]

The Radeon driver is installed by default. Just removing fglrx should get you back to it.
However, there has been a LOT of improvement in the open source drivers just in the last year. It's now pretty damn amazing, but in order to take advange of these improvements you'll need a newer kernel (3.12) and Mesa 10 (Mesa is the OpenGL implementation). Once you have that, you need to put a parameter in your /etc/default/grub file in order to enable the new dynamic power management (dpm) that just hit this year (but won't be default until kernel 3.13).

Kubuntu 14.4 will have all the necessary stuff you need already, such as newer kernel and Mesa 10+. The newer kernel and Mesa CAN be installed in 12.04, but you might be better off just seeing how Kubuntu 14.4 alpha runs on your machine.

Alternatively, you could try out a rolling release distribution. You'll always get the newest graphics (and other) improvments right away, and won't have to worry about Catalyst breaking all the time.

[Pocket]

I thought the power management thing was only important if you have a laptop.

And just so we're clear, then, I won't even be able to upgrade to a newer driver until I've replaced the kernel? I'm not in a huge hurry to get that doubled framerate I've been hearing about; I just want to see if I can run Source games at all without Catalyst, and I know the version of Radeon that came with my install won't do it.

[Benjamin]

Well actually, the dynamic power management is not just for laptops. It makes a really big performance improvement too. Without it, older cards will default to a high clock speed (but not the highest possible). Newer cards will default to the lowest clock speed. This means that newer cards get the most benefit from DPM, but older cards will get a boost as well. I belive the DPM stuff is also clocking the GPU memory clock, not just the GPU clock. It makes a BIG difference!

And yes, you really need the new kernel. A lot of these optimizations, including DPM, VDPAU and HDMI Audio, rely on some new kernel code.

I have an A10-5800K APU myself, which should be on par with a mid range HD6000 series GPU. I'm not sure what you have, but I can play all the source games at 1080p and medium to high effects (minus AA).

If you have access to a spare HD, I think your best bet is to try a seperate install of a newer distribution and just see how it runs.

[Pocket]

Meh. My Linux install is my spare hard drive. If I install the 14.04 alpha, will I be able to smoothly update to the finished version or will that require yet another install from scratch?

[Benjamin]

I ran Ubuntu for a few years, so I would say yes. However, you have a really high chance of running into breakages leading up to the final betas and full release. You MAY be fine, but you probably want to keep a close eye on the Ubuntu alpha/beta forums before doing any upgrades.

Then again, Ubuntu hasn't been making many radical changes to their Desktop OS this cycle since it will be an LTS, so it's probably fairly safe. Check the Ubuntu forums and see how people are liking it. You could always do a dual-boot alongside your current Ubuntu install, providing you have the HDD space.