CUDA issue - how to clean install CUDA in Win 10 to resolve cudaGetDevice() failed

1. download and install Anaconda (Python 3.7): https://www.anaconda.com/distribution/

2. in Command Prompt:

conda update conda
conda update python

conda create --name tensorflow-gpu
conda activate tensorflow-gpu
conda install pip jupyter
pip install tensorflow-gpu
conda install cudatoolkit=10.0 -c pytorch

3. in Start menu select Anaconda3 (64-bit) -> Jupyter Notebook (tensorflow-gpu)

import tensorflow as tf

%%time
with tf.device('/CPU:0'):
    a = tf.random.uniform([1000,1000])
    b = tf.random.uniform([1000,1000])
c = tf.matmul(a, b)

Wall time: 18.9 ms

%%time
with tf.device('/GPU:0'):
    a = tf.random.uniform([1000,1000])
    b = tf.random.uniform([1000,1000])
c = tf.matmul(a, b)

Wall time: 2.99 ms

This is mostly an extended comment, since @diego ask for updates...

I now CUDA 10.0 installed and the nVidia control panel reports nvcuda.dll as v 10.0.132

I have built the recommended demo devicequery.exe using Visual Studio 2017 from the vs solution in C:\ProgramData\NVIDIA Corporation\CUDA Samples\v10.0\1_Utilities\deviceQuery (note that the .exe ends up in C:\ProgramData\NVIDIA Corporation\CUDA Samples\v10.0\bin\win64\Debug)

The program then ran from a cmd prompt and gave the following output.

devicequery Starting...

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

Detected 1 CUDA Capable device(s)

Device 0: "GeForce GTX 1080 Ti" CUDA Driver Version / Runtime Version 10.0 / 10.0 CUDA Capability Major/Minor version number: 6.1 Total amount of global memory: 11264 MBytes (11811160064 bytes) (28) Multiprocessors, (128) CUDA Cores/MP: 3584 CUDA Cores GPU Max Clock rate:
1607 MHz (1.61 GHz) Memory Clock rate:
5505 Mhz Memory Bus Width: 352-bit L2 Cache Size: 2883584 bytes Maximum Texture Dimension Size (x,y,z) 1D=(131072), 2D=(131072, 65536), 3D=(16384, 16384, 16384) Maximum Layered 1D Texture Size, (num) layers 1D=(32768), 2048 layers Maximum Layered 2D Texture Size, (num) layers 2D=(32768, 32768), 2048 layers Total amount of constant memory: 65536 bytes Total amount of shared memory per block: 49152 bytes Total number of registers available per block: 65536 Warp size:
32 Maximum number of threads per multiprocessor: 2048 Maximum number of threads per block: 1024 Max dimension size of a thread block (x,y,z): (1024, 1024, 64) Max dimension size of a grid size (x,y,z): (2147483647, 65535, 65535) Maximum memory pitch:
2147483647 bytes Texture alignment: 512 bytes Concurrent copy and kernel execution: Yes with 2 copy engine(s) Run time limit on kernels: Yes
Integrated GPU sharing Host Memory: No Support host page-locked memory mapping: Yes Alignment requirement for Surfaces: Yes Device has ECC support:
Disabled CUDA Device Driver Mode (TCC or WDDM): WDDM (Windows Display Driver Model) Device supports Unified Addressing (UVA): Yes Device supports Compute Preemption: No
Supports Cooperative Kernel Launch: No Supports MultiDevice Co-op Kernel Launch: No Device PCI Domain ID / Bus ID / location ID: 0 / 1 / 0 Compute Mode: < Default (multiple host threads can use ::cudaSetDevice() with device simultaneously) >

deviceQuery, CUDA Driver = CUDART, CUDA Driver Version = 10.0, CUDA Runtime Version = 10.0, NumDevs = 1 Result = PASS

What did I do to achieve this? Hard to be specific because I didn't realise I had succeeded, but I recall setting the display driver to VGA, rebooting (twice for safety) then uninstalling CUDA 10.0, rebooting then installing 10.0.

I did just notice that I built deviceQuery with a vs 2012 solution, but I did agree to VS updating on solution open.