The default strategy is autodetermined by CuDNN’s strategy selector (it’s not always PRECOMP_GEMM and cudnn has some smart heuristics about it).
You can kick-in the CuDNN autotuner (that runs all the algorithms on your problem size and picks the best one) by adding this line somewhere; torch.backends.cudnn.benchmark = True
See https://github.com/pytorch/examples/blob/master/imagenet/main.py#L111 27 for example.
We have not exposed specific algorithm selections at the python level.