It generally installs MKL if you install a wheel (i.e. 'pip install numpy') these days, which dynamic dispatches based on the processor. It's been criticised a

It generally installs MKL if you install a wheel (i.e. 'pip install numpy') these days, which dynamic dispatches based on the processor. It's been criticised a bit though because MKL doesn't perform as well on AMD hardware without setting some environment variables in the older versions, although it looks like they've added kernels that target AMD hardware recently.