Sorry, but I still do not get it: when I install from binaries, without installing CUDA and cuDNN myself, I still can choose different CUDA versions from the download screen. For example for conda and python 3.6 on Linux it is the choice between these:

conda install pytorch torchvision -c pytorch   # 8.0
conda install pytorch torchvision cuda90 -c pytorch  # 9.0
conda install pytorch torchvision cuda91 -c pytorch  # 9.1
conda install pytorch-cpu torchvision -c pytorch # none

And for pip and python 3.6 on Linux between:

pip3 install http://download.pytorch.org/whl/cu80/torch-0.3.1-cp36-cp36m-linux_x86_64.whl 25

pip3 install http://download.pytorch.org/whl/cu90/torch-0.3.1-cp36-cp36m-linux_x86_64.whl 15

pip3 install http://download.pytorch.org/whl/cu91/torch-0.3.1-cp36-cp36m-linux_x86_64.whl 12

pip3 install http://download.pytorch.org/whl/cpu/torch-0.3.1-cp36-cp36m-linux_x86_64.whl 7


So for each cuda version or none i get a different binary. But why would I want to e.g. choose the cuda 8.0
over the cuda 9.0 version there? And if it always works, even on a CPU if I just make sure not to use cuda
in that case, could I simply always install the version with most recent cuda (9.1 currently) and be happy?
Originally I thought I have to choose the cuda version I have installed on my system, but since this is not the case, why do I have to choose at all?