Multiple Cards

Hi, I am running windows 7 64 bit with two cards, a GTX 280 and a GTX260, and the latest driver, 197.45. The NIVIDA control panel sees both cards, but when I call clGetDeviceIDs it only returns one card. When I look at my system stats using GPU-Z, it detects both cards but indicates that only the one connected to the monitor is enbaled for OpenCL/Cuda/DirectCompute. If I plug the monitor into the other card then this is the one with OpenCL enabled. As expected clGetDeviceIDs will then return only that card. Obvisouly I must be missining something here, but I couldn’t google solution.

The only thing I could think off is that I installed the second card after I had installed the drivers with the first card. I will go ahead now an reinstall the drivers with both cards in their slots.

You may try to put plug on second card video output and extend desktop on it. Also my cofigure one card as physX device. Maybe something wrong with opencl installation. Which sdk are you using?

Ok, reinstalling the drivers actually fixed it. So here is what happened… I got the PC with a GTX260 installed with some older, out of the box driver. I upgraded to the latest driver, 197.45, right away and my OpenCL apps ran fine. Then I installed a GTX280, rebooted and the above problem occurred. Now, after cleaning the drivers using driversweeper and reinstalling , both cards now show up in the call to clGetDeviceIDs. Now the App has problems creating a context, but that may become a different post.

BTW, I am using the stream sdk headers and lib files.

From the NV control panel, enable PhysX on the card that isn’t used for display.

OpenCL developper driver are the 197.13 and not yours plus GT260 are only supported in SDK 3.0 if i remember well…

So u need to reinstall SDK + Driver:

http://developer.nvidia.com/object/cuda_3_…ds.html#Windows

and to run make a list of devices in your context, multi command aueue, and launch

That’s i do with my Ati platform ++

OpenCL developper driver are the 197.13 and not yours plus GT260 are only supported in SDK 3.0 if i remember well…

So u need to reinstall SDK + Driver:

http://developer.nvidia.com/object/cuda_3_…ds.html#Windows

and to run make a list of devices in your context, multi command aueue, and launch

That’s i do with my Ati platform ++