Hello, I am not that up on gaming but enjoy to game when can, wore out an awesome Dell XPS and just purchased my Alienware 17 to replace it. I did not get it with a CD tray as I figured now that everyone uses memory sticks etc and downloads everything straight from the internet I wouldn't need it...BUT... I purchased the new Doom and Fallout4 and when I went to install Doom it told me I don't have the space...kind of crazy since noting else has been loaded yet and it would appear that I have all the room in the world, For Fallout 4 it looks like I have the room but then will be definitely to full for Doom. Don't get it?? On the old XPS of course the disc went in the tray each time played and now I am needing to load the whole game...is that my problem?? Should I buy a portable disc drive so I can do it like before or do I need to pick up a portable Hard drive like a 2Terabite so I can just download the games to it and plug it in when play? Let me add that when I play most of the time I do not have an internet connection so everything must be installed. Not worried at all about multiple player online gaming right now. Just want to get going on these new games!! Thanks for the Help!!