Have always used my last "junker" ( a computer that I had just replaced for regular work/home use) on board. I upgrade those every 3 years if that makes a difference. I have always used regular laptops and store them in a Pelican Computer case when not underway. They do eventually die but have managed to get 2-3 years more use out of them so far. I used to just take the home laptop to and from the boat with the map software in it. Was nice cause I could work on routes at home and didn't have to transfer the waypoints and all but now I just use my USB key. Russ