4 Replies Latest reply: Feb 4, 2014 3:37 AM by reapster RSS

Xinerama stops OpenCL seeing my two GPUs

logicethos Newbie
Currently Being Moderated

I have two 7950 in my Linux PC.


#:~$ aticonfig --lsa


* 0. 01:00.0 AMD Radeon HD 7900 Series

   1. 07:00.0 AMD Radeon HD 7900 Series


If I switch Xinerama on, then OpenCL can only see 1 gpu.  Here is what cgminer says:


#:~$ cgminer -n

  [2013-06-15 15:35:36] CL Platform 0 vendor: Advanced Micro Devices, Inc.                   

  [2013-06-15 15:35:36] CL Platform 0 name: AMD Accelerated Parallel Processing                   

  [2013-06-15 15:35:36] CL Platform 0 version: OpenCL 1.2 AMD-APP (1113.2)                   

  [2013-06-15 15:35:36] Platform 0 devices: 1                   

  [2013-06-15 15:35:36]  0       Tahiti                   

  [2013-06-15 15:35:36] 1 GPU devices max detected


Switch Xinerama Off, and it can see the two gpu's.  The dev for cgminer says it's because Xinerama mode creates one virtual screen, and OpenCL for some reason looks at the "Screen" rather than "Device" configuration.

  • Re: Xinerama stops OpenCL seeing my two GPUs
    himanshu.gautam Master
    Currently Being Moderated

    Thanks for reporting the issue. I will to reproduce it here, and report back to you.


    Himanshu , Bruhaspati


    The information presented in this document is for informational purposes only and may contain technical inaccuracies, omissions and typographical errors. Links to third party sites are for convenience only, and no endorsement is implied

More Like This


  • Correct Answers - 4 points
  • Helpful Answers - 2 points