MATLAB couldn't find my gpu any more

I have got a GTX 560.(win7_64, MATLAB 2012a,cuda 4.2, vs2010, windows sdks 7.1) Two days ago, i run some short and simple codes(eg: gpuDevice, gpuArray, gather) for test, and it's all right then. Then i downloaded the nvmex.m, and compiled a few .cu files. But now, something has really astonished me: when i run gpuDevice again, it tells me: Error using gpuDevice (line 26) No supported GPU device was found on this computer. To learn more about supported GPU devices, see www.mathworks.com/gpudevice.

the ans to gpuDeviceCount is 0.

How could it be that?

PS: as i am a new hand in programming, a detaied answer will be totally be appreciated. Thank you

[Walter Roberson]

See also http://www.mathworks.co.uk/matlabcentral/answers/43239#answer_54809

Answer 1

[Edric Ellis]

Firstly, I don't know of any good reason why installing nvmex should have any effect on whether the GPU stuff works in MATLAB.

That specific error message implies that we could communicate with the CUDA driver OK, but that the driver told us there were no GPUs we could use. One thought is that something similar can happen if you attempt to use a (non-Tesla) GPU when connected through Windows Remote Desktop - are you doing that?

One other useful piece of information would be: what's the output of running

    parallel.internal.gpu.CUDADriverVersion

[Wolfgang Garn]

I have a similar problem after running " G = gpuArray(magic(6));" returns with the message: "No supported GPU device was found on this computer."

The command parallel.internal.gpu.CUDADriverVersion returns 8.17.13.623 (306.23). I have a Nvidia GeForce GT 620, which is supposed to be supported.

I use Windows Remote Desktop - your message suggests that this is the root of the problem. Can I use the GPU capabilities using a remote connection? How?

[Jason Ross]

Use VNC instead of Remote Desktop. Depending on the GPU, the driver can only be loaded in WDDM mode or TCC mode. If you can't use TCC mode, the GPU becomes unavailable using RD.

http://http.developer.nvidia.com/ParallelNsight/2.1/Documentation/UserGuide/HTML/Content/Tesla_Compute_Cluster.htm

[Rohit]

Hi - I am having similar issues with GPU and remote desktop. As suggested by Jason I installed VNC, but Matlab still refuses to identify my GPU. Any help will be helpful.

Answer 2

[Rohit]

Hi - I am having similar issues with GPU and remote desktop. As suggested by Jason I installed VNC, but Matlab still refuses to identify my GPU. Any help will be helpful.