I have used CUDA for one month on my computer and it works good all the time, yesterday I found that it can not find CUDA, when I runned deviceQuery, the results comes out as:
CUDA Device Query (Runtime API) version (CUDART static linking)
There is no device supporting CUDA.
Device 0: "Device Emulation (CPU)"
CUDA Capability Major revision number: 9999
CUDA Capability Minor revision number: 9999
Total amount of global memory: 4294967295 bytes
Number of multiprocessors: 16
Number of cores: 128
Total amount of constant memory: 65536 bytes
Total amount of shared memory per block: 16384 bytes
Total number of registers available per block: 8192
Warp size: 1
Maximum number of threads per block: 512
Maximum sizes of each dimension of a block: 512 x 512 x 64
Maximum sizes of each dimension of a grid: 65535 x 65535 x 1
Maximum memory pitch: 262144 bytes
Texture alignment: 256 bytes
Clock rate: 1.35 GHz
Concurrent copy and execution: No
Run time limit on kernels: No
Integrated: Yes
Support host page-locked memory mapping: Yes
Compute mode: Default (multiple host threads can use this device simultaneously)
Test PASSED
I have updated the SDK and tried reinstall driver after toolkit, but it fails anyway. Is there any reason that can result in such a situation.
I am not a MAC users but I had similar problems under Linux.
The trick is to load the X server with all the windows managers and than log out of the X. In console mode, the nvidia driver will still be loaded and the cuda device will be on. I had to use this to get the cuda-dbg working.
When you first boot up the system in console mode, the nvidia driver is not loaded and the GPU device is not available. One benifit of this , is that more host memory is free.
Or the card has to be remove and inserted back. This happened also. :mellow:
A bad setting of the attributes of the device file /dev/nvidia* is likely to generate a similar problem on a linux box (maybe on a macosx box too).
Be sure the users that are using cuda have a read/write access on the /dev/nvidia* device files.