cuda 7.5 ubuntu 14.04 Quadro K2200/4000: NVRM: RmInitAdapter failed

Trying to have cuda 7.5 working on a ubuntu 14.04 machine.

I installed from deb following instructions:

http://docs.nvidia.com/cuda/cuda-installation-guide-linux/index.html

The Desktop is installed by a Quadro K2200 and a Quadro 4000. Both listed here as GPU valid:

https://developer.nvidia.com/cuda-gpus

I compiled deviceQuery, which shows (even if run as super user):

./deviceQuery Starting...

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

 cudaGetDeviceCount returned 10
-> invalid device ordinal
Result = FAIL

this appears in the syslogs:

[ 2152.593188] NVRM: RmInitAdapter failed! (0x25:0x1c:1379)
[ 2152.593215] NVRM: rm_init_adapter failed for device bearing minor number 1
[ 2152.593248] NVRM: nvidia_frontend_open: minor 1, module->open() failed, error -5

I did run the script shown here, but that did not help:

http://docs.nvidia.com/cuda/cuda-installation-guide-linux/index.html#runfile-verifications

Some details:

cat /proc/driver/nvidia/version

NVRM version: NVIDIA UNIX x86_64 Kernel Module  352.79  Wed Jan 13 16:17:53 PST 2016
GCC version:  gcc version 4.8.4 (Ubuntu 4.8.4-2ubuntu1~14.04.3) 

from /etc/dev, ls -al | grep nvidia

crw-rw-rw-   1 root root    195,   0 Okt 27 17:02 nvidia0
crw-rw-rw-   1 root root    195,   1 Okt 27 17:02 nvidia1
crw-rw-rw-   1 root root    195, 255 Okt 27 17:02 nvidiactl

lspci -vv | grep NVIDIA

03:00.0 VGA compatible controller: NVIDIA Corporation GM107GL [Quadro K2200] (rev a2) (prog-if 00 [VGA controller])
    Subsystem: NVIDIA Corporation Device 1097
03:00.1 Audio device: NVIDIA Corporation Device 0fbc (rev a1)
    Subsystem: NVIDIA Corporation Device 1097
04:00.0 VGA compatible controller: NVIDIA Corporation GF100GL [Quadro 4000] (rev a3) (prog-if 00 [VGA controller])
    Subsystem: NVIDIA Corporation Device 0780
04:00.1 Audio device: NVIDIA Corporation GF100 High Definition Audio Controller (rev a1)
    Subsystem: NVIDIA Corporation Device 0780

cat /etc/modprobe.d/blacklist-nouveau.conf :

blacklist nouveau
options nouveau modeset=0

environment variables:

CUDA_HOME

/usr/local/cuda-7.5

PATH:

/usr/local/cuda-7.5/bin:/usr/local/cuda-7.5/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games

LD_LIBRARY_PATH

/usr/local/cuda-7.5/lib64:

what is the output of

dmesg | grep NVRM

[ 11.159259] NVRM: loading NVIDIA UNIX x86_64 Kernel Module 352.79 Wed Jan 13 16:17:53 PST 2016
[ 13.778528] NVRM: RmInitAdapter failed! (0x25:0x1c:1379)
[ 13.778590] NVRM: rm_init_adapter failed for device bearing minor number 1
[ 13.778615] NVRM: nvidia_frontend_open: minor 1, module->open() failed, error -5