Yes, good question. I bought it because it was recommended for my XPS15. But there is also the 180W version. That would have been enough for a long time and the power supply (external from the TB16 anyway) wouldn't be so clunky. A laptop usually only draws 10-20 watts if you're not watching 7 films at a time, and otherwise charging takes a little longer. Whether your P50 works with it depends only on whether you have a Thunderbolt = USB 3 type "C" plug, the oval one that you can also plug in upside down. If so, the 180W version is also sufficient. Incidentally, the docking station offers various useful connections, but at least in my case no support for transferring the 4k screen of the XPS15 to an external 4k Samsung UE55JS8580, which was promised somewhere on the net (don't forget, the original TB15 was suddenly withdrawn from the market for reasons that are not entirely transparent).