Update (Oct 2013):
For anyone who stumbles across this, I've
posted an update
where I got the proprietary driver to work acceptably (but only on single screen).
After researching and asking around on forums about GPUs and Linux,
I decided to get an AMD Gigabyte HD7770 1GB
as an experiment. From what I could gather, AMD support in Linux was pretty bad,
(or at least, more problematic than nVidia cards), so I went in
with low expectations, willing to wear the difference of flogging
it off secondhand if it didn't work out.
TL;DR: It wasn't all bad, but nothing "just works" (as was
pointed out in forum responses). From my experience, I have to
conclude that the AMD Linux drivers are effectively broken at the
moment.
Rationale
Despite being warned away from AMD cards, the 7770 is an entry-level
gaming card and not overly expensive. It was also overkill for the
games I expect I would be trying to play (of which there isn't a
huge selection on Linux yet anyway).
Since it wasn't too expensive ($119), I was willing to take the risk
and try it out, partly for the chance to experiment, partly because
AMD are reckoned to be good value for money in that price range, and
partly because AMD at least supports an open source driver (for varying
degrees of "supports").
Machine and OS Specs
Hooked into the i5 3470 system
I built in December 2012, running LinuxMint 14 (Nadia) Cinnamon 64-bit.
On with what I found.
Card Installation
Quick and easy. Dropped right into the PCI-E slot without the
firm coaxing that RAM and SATA cables usually need. I chose the
second port because it looked like the USB 3.0 cable might get
in the way of the card. After I put it in, I thought it probably
wouldn't have been a problem, but I left it where it was.
Plug in the 6-pin power cable and away we go.
Note: If I'd got the slight less powerful 7570 (which I was considering)
I wouldn't have needed the power, but I got a beefy PSU and it
seemed a shame to not try out some of those cables sitting around
in the bottom of the case).
With the GPU plugged in the on-board graphics is disabled. This is
(I gather) expected behaviour.
Open Source AMD Video Driver
Single Screen
After plugging in the GPU and booting up, I didn't have have to do
anything in particular. LinuxMint 14 has drivers installed by default
to drive the GPU.
First test I plugged into the DVI port. It started up fine at full
resolution.
A command you can use to see how the system has detected your GPU
is:
lscpi --nn | grep VGA
Mine displayed "[Radeon HD 7700 Series]"
Dual Screen
Then I added in the second monitor. If you've ever heard someone
claim the dual-monitor support in Linux is limited, you can believe
them.
Initially with both plugged in, only the HDMI monitor would work.
The other monitor (plugged into the DVI, which was originally
working), displays its "Current input timing not supported by
monitor display" message.
I worked out how to get things going by using xrandr, a
command-line tool that configures the displays.
By itself, executing xrandr outputs details about the detected
displays. You need to know the "names" the system has given the monitors
plugged into each port in order to control their output settings. In
my case, the monitor plugged into the DVI port was "DVI-0", and the
one plugged into the HDMI port "HDMI-0".
To make my main screen on the left and the second screen on the
right, I used the following command:
xrandr --output DVI-0 --auto --output HDMI-0 --auto --right-of DVI-0
This works, but leaves the taskbar on the right hand side screen
(HDMI-0 in this case). To make the system use a particular screen
as the "primary", use the
following command:
xrandr --output DVI-0 --preferred --auto --primary
This shifts the taskbar to the DVI-0 display.
Saving Dual Screen Setup -- Attempt 1
So, after using these commands to set up the displays as desired,
I had to work out how to make the changes permanent. The "normal"
way to do this (if that's the right word) is to put the configuration
into the /etx/X11/xorg.conf file.
Using
this answer,
I adapted a minimal
xorg.conf file and came up with this:
Section "Monitor"
Identifier "First monitor"
Option "PreferredMode" "1920x1200"
EndSection
Section "Monitor"
Identifier "Second monitor"
Option "PreferredMode" "1920x1080"
Option "RightOf" "First monitor"
EndSection
Section "Device"
Identifier "Radeon HD 7700 Series"
Driver "radeon"
Option "DVI-0" "First monitor"
Option "HDMI-0" "Second monitor"
EndSection
Something went wrong when I ran it though. At least, the HDMI-0
monitor got a new name, and became "HDMI-3". So it didn't quite work.
Saving Dual Screen Setup -- Attempt 2
Next I thought I'd try and set things up with xrandr, then go into
the Preferences/Display dialog and use the "Keep current configuration"
option to save the setup.
This creates a monitors.xml file in ~/.config with
the current settings. However, it only applies after you login.
The HDMI screen, if plugged in, always seems to be considered the "primary".
Saving Dual Screen Setup -- Give Up
I tried a couple of other wild and fancy things that I found on
various sites to set up dual screens, but in the end just gave up.
No matter which way I plugged the monitors in, if the smaller 23"
LCD was attached, it was the one that "lights up" for the splash
screen. After login the 24" came to life, but not before.
I couldn't work out how to get both screens going at the system level,
rather than the user level, so I gave up.
Open Source Driver Performance
First test was running a fullscreen 1080p video. It ran with lots
of glitches and jaggies when playing. The CPU went up to 50-55
degrees on all cores -- was is actually processing in software?
Then I downloaded the Phoronix Test Suite. The suite package itself
is reasonably small, but the full test suite takes over 5GB of download
and can take a few hours. I managed to run a few of them, but none
of them ran very well. For example, Nexuis looked like it was running
at about 0.1 FPS.
It was clear that, unfortunately, the open source driver was not
even close.
Proprietary AMD Video Driver
It seemed I could choose between the Catalyst driver from AMD's
site, or one of the fglrx drivers that were listed in the software
centre. I still haven't worked out what the difference between
these two things is -- I think they're related in some way, but
I'm not sure how.
So after looking at askubuntu.com/questions/142627,
I did:
sudo apt-get install fglrx-updates flgrx-amdcccle-updates
Bam! Upon reboot, the video was completely broken. I could see the
motherboard post, and then nothing -- not even a prompt. The onboard
video also wasn't working (at the time I didn't realise you have to
unplug the GPU completely for the motherboard to activate the
onboard video).
So, at a loss, I booted up and started typing blind the following
steps:
- Reboot
- Ctrl-Alt-F1 (open a console, that wasn't visible at all)
- Enter username
- Enter password
- sudo apt-get -y remove --purge fglrx-updates
- Enter password again (for the sudo)
- <wait>
- sudo reboot
Fortunately, this fixed the problem. So I can't really recommend
installing the fglrx-updates variant of the driver.
Next I tried installing the Linux Catalyst driver from AMD's website.
This was version 12.11beta at the time (see
upubuntu.com/2012/08/install-amd-catalyst-128-on-ubuntu.html
for the steps I followed).
This driver seemed to work fine (it at least didn't black out my screen)
but came with the "beta" watermark in the bottom right. To get rid
of that, follow the instructions at
askubuntu.com/a/216730.
Dual Screen -- Proprietary
Unfortunately, getting dual screens set up with the proprietary driver
was, if anything, more difficult than with the open source driver.
I tried the following mechanisms:
- Steps at unixmen.com/howto-install-ati-driver-in-ubuntu
- Then superuser.com/questions/395927,
but the Virtual 3820
caused tearing when the taskbar animated up
- Then I used arandr to get the 2nd display going
- Then I tried the amdcccle (admin) application to apply
"Digital Monitor(2) -> Adjustments -> Scaling (0%)"
This resulted in another refresh problem on the second monitor,
where it would only update while the taskbar on the primary
screen was animating during hover.
So I gave up on the dual screen idea in order to get some testing done
for the driver. With the dodgy dual screen setup, running the
test application fgl-glxgears got 500-600 FPS, but was very choppy.
Proprietary Driver Performance
To revert to a single screen, I entered the following at the command
line:
aticonfig --initial -f
Now running fgl-glxgears got around 2500-3000FPS. So, same driver but
running with only a single screen instead of dual screen improved the
performance of this benchmark application by 6x, and it no longer
looked choppy. But this is a pretty simple little application, I wanted
something with a bit more meat.
So I installed xonotic and ran it up fullscreen (1920x1200) with the
highest settings I could set. Within the game is ran just fine
(too fast for my old hands), but my old eyes couldn't discern any
difference between the "default" versus the "high" settings, so I'm
not sure if I did it right.
But, after running this (or, it seemed, any "fullscreen" game),
the taskbar animation back in the desktop became choppy and caused
tearing all over the screen.
Last Ditch
All this playing had taken a couple of weeks by this stage. I got
recommended to run the sgfxi script at smxi.org
(a "fix it all" graphics driver script). When I downloaded it and ran, it exited
saying I needed to run it from outside X.
Which was fine, I thought, so I tried to Ctrl-Alt-F1 into a console.
But I couldn't see the console, at all. I could see the X session,
but none of the TTY console (1 through 6) were working.
Somewhere along the way I'd borked those. By this time I'd had
enough "experimentation".
Blew away Mint. I'm now running Xubuntu with the onboard video.
Anyone want to buy a barely used Gigabyte HD7770?
Conclusion
My experience has led me to conclude that both the open source
and proprietary drivers for AMD GPUs on Linux are broken.
The Intel drivers for the onboard video aren't without their quirks
(for example, I find it really hard to configure the login screen
to start on a specific monitor at a specific resolution, and setting
up dual monitors is still a bit of a chore). But for the most part
they work.
With the AMD proprietary drivers I had crashes, no screen at all for
a while, and dual screen setup was diabolical. With the open source
driver I had tearing and I wasn't quite sure it was actually using
the GPU to do anything.
Hopefully I'll get an nVidia card at some point to get another
perspective, but I'll be starting with pretty low expectations.
