I tried using mxnet-cu92 1.5.0 and both GPUs work now. I’d however like using cuda 10.2 as I have other stuff that use it (and it bugs me that I don’t know what I’m doing wrong).
I think the problem comes from something that happened between mxnet 1.5.0 and mxnet 1.6.0. I checked the release notes of 1.5.1 and 1.6.0. and the only change that seems relevant to me is https://github.com/apache/incubator-mxnet/pull/15449. Has something else changed in between that I should check?
I tried using mxnet 1.6.0 and downgrading to cuDNN v.7.6.5.32 (had v8.2.2.26 before) but it didn’t help.
Also found a similar discussion Using mxnet with CUDA freezes python