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I have downloaded the latest AMD/ATI drivers for my Radeon HD 7850 and I am having a difficult time getting it to work with ATI Stream SDK 2.1.

I have tried purging fglrx and installing from debs created from the Catalyst installation script. I have also tried simply installing directly from the script, vs generating and installing .debs. After every installation, I run sudo aticonfig --initial --nobackup and then reboot my system.


The problem I am having is that fglrxinfo is giving me this error: Error: unable to open display (null). I have run fglrxinfo with my DISPLAY variable set to both :0.0 and :0 with no success.

Also, DISPLAY=:0.0 ./CLInfo only returns my CPU and no GPU. My goal is to install my graphics card and have it shown in CLInfo so that I can use it for OpenCL.

System Information

$ lspci -nn | grep VGA
01:00.0 VGA compatible controller [0300]: Advanced Micro Devices [AMD] nee ATI Device [1002:6819]

$ uname -a
Linux Ubuntu-12.04 3.2.0-35-generic #55-Ubuntu SMP Wed Dec 5 17:42:16 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux

$cat /etc/X11/xorg.conf
Section "ServerLayout"
    Identifier     "aticonfig Layout"
    Screen      0  "aticonfig-Screen[0]-0" 0 0

Section "Module"

Section "Monitor"
    Identifier   "aticonfig-Monitor[0]-0"
    Option      "VendorName" "ATI Proprietary Driver"
    Option      "ModelName" "Generic Autodetecting Monitor"
    Option      "DPMS" "true"

Section "Device"
    Identifier  "aticonfig-Device[0]-0"
    Driver      "fglrx"
    BusID       "PCI:1:0:0"

Section "Screen"
    Identifier "aticonfig-Screen[0]-0"
    Device     "aticonfig-Device[0]-0"
    Monitor    "aticonfig-Monitor[0]-0"
    DefaultDepth     24
    SubSection "Display"
        Viewport   0 0
        Depth     24
  • Ubuntu 12.04 (Server)


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up vote 1 down vote accepted

I was able to get everything working by installing a lightweight X Window system.

sudo apt-get install lxde

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