1 Reply Latest reply on Mar 5, 2014 12:03 AM by amd_support

    OpenCL console mode -> screen flickering




      I have some issues running an OpenCL program from the Linux console. I already learned from [1] that the program needs to have root privileges and the X window system needs to be stopped.

      But immediately after the program starts, the screen begins to flicker. After the program has finished the flickering still continues. I assume this is not caused by my program because I got the same effect when running samples from the APP SDK or just 'clinfo'.


      Does anyone know how to fix this?


      [1] OpenCL with no X-server on Linux



      System info:

      Number of platforms:    1

        Platform Profile:     FULL_PROFILE

        Platform Version:     OpenCL 1.2 AMD-APP (1411.4)

        Platform Name:        AMD Accelerated Parallel Processing

        Platform Vendor:      Advanced Micro Devices, Inc.

        Platform Extensions:  cl_khr_icd cl_amd_event_callback cl_amd_offline_devices cl_amd_hsa


        Platform Name:        AMD Accelerated Parallel Processing

      Number of devices:      2

        Device Type:          CL_DEVICE_TYPE_GPU

        Device ID:            4098

        Board name:           AMD Radeon R7 Series


        Platform ID:          0x00007fda166ef500

        Name:                 Spectre

        Vendor:               Advanced Micro Devices, Inc.

        Device OpenCL C version:  OpenCL C 1.2

        Driver version:       1411.4 (VM)

        Profile:              FULL_PROFILE

        Version:              OpenCL 1.2 AMD-APP (1411.4)

        • Re: OpenCL console mode -> screen flickering

          Hi h_I,

              I ran the clinfo from console but I didn't observe any flickering in my machine. I took the following steps

              From console:

              1. Disabled any running Xserver using "sudo /etc/init.d/lightdm stop".

              2. Ran sudo clinfo. It lists both CPU and GPU without flikring.

              (Tested on Radeon HD 6570 with AMD FX 4100, and driver 1359.4)