I can speak of my HP ZBook (running windows still but I hope not for long), I send it to a shop for swaping the i5 it had for an i7 and still beats most newish mid range laptops sold these days. It is a 17inch G2 model and still works great despite it being more than 6 years old, and it is M2 enabled. I think it could be a good Linux machine in the future
Specs from the top of my head because I am lazy to go and fetch it:
i7 4th gen (I do not know nothing about models, sorry)
32gb of ram
Nvidia k5100 with 8GB of video ram
I have 2 storage drives on it, an M2 with 256GB and a platter disc with 500gb and I still can install a 3rd one but I do not see the point
It has: The Clit(TM)
Sadly is not the full hd model, but I am happy with the 900p ( I think?) screen it has. I could also recommend one of these if you find it for cheap. Mine cost me about $250, it has some scratches and dents as the body is mostly aluminum but nothing that could impede the machine from work.