Gaming Laptop Docking Station

Hi, I will be leaving for college next year and I'm planning on buying a laptop for the journey. I am a semi-avid pc gamer, and I plan on buying a full desktop replacement machine. I want to be able to bring it to class/library/home on the weekends/work, but I also would like a desktop setup in my dorm. I prefer a traditional keyboard, mouse, monitor setup to a laptop setup, especially for gaming. Also, the dorms do not have wireless internet, but there is Ethernet access. I am drooling over some asus laptops on newegg, but there are no compatible docking stations I can find besides the belkin universal one. I have two questions. Do docking stations hinder performance compared to directly plugging in a monitor, mouse, and keyboard to a laptop, and what options are available (including other brands of laptops with a compatible docking station.) Thanks!

-DVI Monitor, USB Keyboard/Mouse
-It will most likely use vista