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Originally posted on

I have a laptop with an Nvidia GeForce 630M graphics card running on Ubuntu 12.04.

Running lspci | grep -i nvidia I get the following line

01:00.0 VGA compatible controller: NVIDIA Corporation GF108M [GeForce GT 630M] (rev al)

and according to my graphics card is compatible.

After compiling the samples and running the deviceQuery I get the following output:

CUDA Device Query (Runtime API) version (CUDART static linking)

cudaGetDeviceCount returned 10
-> invalid device ordinal
Result = FAIL

I read online that this error is because my graphics card is not compatible.

If I run jockey-gtk to check the Additional Drivers I get the following list

nvidia_current (Enabled)
NVIDIA binary Xorg driver, kernel module and VDPAU library (Not Enabled)
Experimental NVIDIA binary Xorg driver, kernel module and VDPAU library (Not Enabled)

When I select tne nvidia_current I get at the bottom a green button and This driver is activated but not currently in use

I downloaded CUDA 5.5 as a .deb package and followed the instructions posted on the website


After running nvidia-smi -a as Robert mentioned in the comment I get the following output

NVIDIA: could not open the device file /dev/nvidia0 (Input/output error)
Unable to determine the device handle for GPU 0000:01:00.0: Unknown Error

How can I possibly fix it?

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I have the same problem with you. This is what I've done to make it work properly:

  1. Create new module blacklist

    # touch /etc/modprobe.d/nvidia-installer-disable-nouveau.conf
  2. Now blacklist nouveau

    # echo -e "blacklist nouveau\noptions nouveau modeset=0" > /etc/modprobe.d/nvidia-installer-disable-nouveau.conf
  3. Restart your PC / Laptop

  4. If the problem persist, reinstall your NVIDIA driver, make sure you have downloaded the latest NVIDIA driver from here‎. Save it anywhere and change its permission to executable with this command

    # chmod +x NVIDIA-Linux*
  5. If you have problems with building new NVIDIA module, install kernel header with this command

    # apt-get update; apt-get install linux-headers-$(uname -r)
  6. Now reinstall your NVIDIA using this command

    # ./NVIDIA-Linux{your version}
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