Thanks for replying @ptrblck!  While trying to reproduce the error at home (I was at work when I first got the error) I started with a smaller batch size (I was using 1024), and lo and behold it worked!  I did some investigating, and apparently 1023 works, but any batch_size >= 1024 causes that error.  It seems to me that it’s a GPU memory issue, but I don’t know why I’m not getting the traditional RuntimeError: CUDA out of memory.  I’ll double-check that this is the case on my work setup as well, and will reply back tomorrow.