I have a server (CentOS6) which has an ATI GPU. For users to have access to this GPU for computation with OpenCL, they need to have an X session open unfortunately (a restriction on the ATI driver). These users will ssh to the server.

How is it possible for them to start a "dummy" X session on the GPU so that they can access it for computation? (ssh -X server and launching an app like xclock or whatever does not start an Xsession on the GPU...)

Thanks a lot in advance.

2 Answers 2


Follow this document: http://developer.amd.com/sdks/AMDAPPSDK/assets/App_Note-Running_AMD_APP_Apps_Remotely.pdf

After that, first set the system runlevel to 3 (you may use /etc/inittab under centos). Then, reboot the system and connect to the system by a new session through SSH. Finally before running OpenCL applications: 1) run 'init 5' command 2) run 'export XAUTHORITY=$HOME/.Xauthority' command


If they have the access rights to do so, the remote user should just be able to run something like

X :0 &

The remote user should then be able to run the Bitcoin miner.

If you aren't running a Bitcoin miner, you really should think about switching to an NVIDIA GPU.

  • Just curious, why switch to NVIDIA? Aug 13, 2012 at 20:18
  • @TomMarthenal AMD GPUs can't do OpenCL without being run under X. This is a limitation of AMD's driver design. NVIDIA GPUs can run compute jobs without having X running. May 20, 2013 at 4:58

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