Only CPU is accessible via OpenCL on 3770K

[Timofey_C_]

Hi all,

I'm running Windows 7 x64 and have i7 3770K installed with built-in HD 4000 graphics. Intel OpenCL dlls and SDK are both installed on my system. However, for some reason only CPU is accessible via OpenCL. Intel OpenCL samples return -1 when run with -g. GPU caps viewer also shows that there is only 1 device on Intel OpenCL platform. GPU-Z shows that HD 4000 does not support OpenCL.

I also have AMD Radeon HD 7970 installed in my computer, however, the monitor is connected to the output of HD 4000 (Radeon is accessible via OpenCL even in headless mode).

Tried to disable Radeon in Windows device manager, but that does not help.

How to troubleshoot this further and/or fix it?

Thanks

[Timofey_C_]

The only thing I have not tried before was complete uninstallation of AMD drivers, so it's probably the key to the puzzle.

[Raghupathi_M_Intel]

That may be the issue since you have both amd and intel listed in your registry. We might have to try to reproduce and debug this on our end. But I am glad you now have both the devices.

Thanks,
Raghu

[Michael_Chou]

I have done some experiments about this.
(Win7/Win8) No matter you have switchable graphics or a discrete GPU, if you have AMD driver installed, HD4000 will not be accessible as a OpenCL device. If you uninstalled AMD driver (no need to remove the discrete GPU card), HD4000 will be accessible again.

I have seen reports about behaviors like this but with NVIDIA GPU.

[Timofey_C_]

Seems to be exactly the case, Michael. Did not try with NVIDIA.

[Michael_Chou]

Timofey C. wrote:

Seems to be exactly the case, Michael. Did not try with NVIDIA.

Not yet, I don't have an NVIDIA card.

[Marton_G_]

Hello, I have a such problem with my Core i5 3570K. But I’ve never used any other video card in my computer. I did this: 1. install the HD graphcis driver (9.17.10.2932) 2. install the SDK (intel_sdk_for_ocl_applications_2013_x64_setup and also tried: 2012 version) 3. check for both OpenCL devices under gpu caps viewer Result: I’ve seen CPU only. Do you have any idea how can I fix it?

[Chuck_De_Sylva]

Marton,

Can you check to see that the registry keys mentioned above by Raghu exists (HKLM\Software\Khronos\OpenCL\Vendors)? Also do you see these files in %WINDIR%\System32 folder:

igdfcl32.dll
igdrcl32.dll

IntelOpenCL32.dll
Intel_OpenCL_ICD32.dll

- Chuck

[Marton_G_]

Hello Chuck, Thank you for fast reply. There is one record only: [HKEY_LOCAL_MACHINE\SOFTWARE\Khronos\OpenCL\Vendors] IntelOpenCL64.dll REG_DWORD 0x00000000 ...and all files exist. p.s. sorry for the private message. wrong button... :-)

[Marton_G_]

I found reason of problem. This computer is a server which is always online and it haven’t any peripheries (mouse, keyboard or monitor) So we are working with Remote Desktop. And I don’t know why but when I do this, the OpenCl can’t find my graphics 4000. I had an intuition and I tried our computer with peripheries. And It’s working!!! But this is a big problem because this computer’s job is to make scientific calculates and we have to work with it from anywhere. I hope you will find some solution to this problem.

[Chuck_De_Sylva]

Marton,

Really. It was because there were no peripherals installed? Strange. Did you happen to reboot the server as well? I'm guessing that is more than likely why it is running now.

Thanks, Chuck

[Raghupathi_M_Intel]

The problem is remote desktop not periferals. RD turns off hardware acceleration. When I login to my machine via RD I see only one device and I know that I have both devices available when I launch gpucapsviewer locally.

Raghu

[Raghupathi_M_Intel]

Did you try VNC or someother application to loging to your server remotely?

Thanks
Raghu

[Marton_G_]

I found a lot of page about OpenCl and Remote Desktop conflict. So I have to use another remote service. I treid the LogInMe. It is working perfectly with OpenCl and there is no need install any client. Thank you for your help! Regards, Marton

[onizuka]

connect your monitor to radeon 7970 and press win+p and select extended option for monitor this way both opencl devices will be available to use. but first you need to enable dual monitor from bios settings. opencl should work for intel without selecting extended monitor option but it is a driver limitation from intel as opencl from NVidia and amd works fine on secondry gpu without selecting extended monitor option.