CUDA 5.5, GTX 970, compatibility

I have an old CUDA DLL library built two years ago with CUDA 5.5 and it has been working well with GTX 780 cards. The system is Windows 7, 64 bit. Now I want to make it work on a new machine and I bought a GTX 970 for it. Since my top goal is to not to change the DLL at all, I tried to install CUDA 5.5 on this new machine. Then I got the error message:

“The graphics drive could not find compatible graphics hardware. You may continue installation, but you will not be able to run CUDA application”.

I then continue with it and install a newer version driver independently. However, the DLL does not work and could not find “CUDART64_55.DLL”. I checked my old computer and it should be in under “C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v5.5\bin”. In the new computer, due to the “unable to install problem”, there is nothing under the “C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v5.5”, except for a “doc” folder.

Could someone help me make it work? Any suggestions or tricks is appreciated.

You haven’t installed CUDA 5.5 successfully on the new machine. Run the CUDA 5.5 installer again, deselect the option to install the graphics driver, but leave the other install options intact.

If your only need for CUDA 5.5 is to get this application to work, you could also just install a version of CUDA 6.5 (or CUDA 7.0 RC) that recognizes your GTX 970 GPU, and then manually copy the cudart64_55.dll file from the old computer to the new computer. Put it and the old CUDA DLL in the same directory as the application that uses it, and it should be found by that DLL.

Thanks txbob. I found out that it is because CUDA 5.5 requires a visual studio for toolkit installation. And obviously, I don’t have VS on the new machine.

Here is another question:
Similar to your second advice, if I just install a new driver (but not CUDA 6.5 or 7.0) and copy all the CUDA libraries from the old machine to the new one, will that work?

There are free versions of visual studio.

Yes, your method should work. Install a proper GPU driver on the new machine. Then provide all the libraries needed.

Never mind. It worked, as long as I put the directory into the “Path” environment variable.