Here are the two tests I ran today on 6mm cardboard.
This first one you’ll notice I have a much fuller grid expanding to the right, almost a full box at S3000/P100%
The second one is testing # of passes and depth per pass vs speed.
All the red squares are clean cut through.
Once again this is 6mm cardboard.
So yes, the 1600mw SM2.0 laser can cut through thicker cardboard.
** Edit. my test cardboards are not perfectly flat either. they are misshaped, and the top right corner is not held down, so the whole area is bowing up.