how much power the laptop has. Most of the laptops today have the Sony batteries. Sony batteries were the ones recalled by Dell and the other laptop companies. I have a Sager that lets me use a second battery also. The laptop is a gaming computer with a 17' screen and can get 4 hours of battery life. That's great for a 17" screen and the battery wasn't a Sony so it wasn't recalled for catching on fire like the Sonys.
Due to my problems with other brand laptops, especially battery life,hard to find driver,poor service,strike on high temperature, etc., my wife and me both use DELL now. I often use 2nd battery that replaces the DVD drawer. After I get back home, whole night I can stay on the laptop without AC. Dock station is cheap on Ebay, and I can use external monitor - previous other brand laptop can't after I upgraded OS.
My D620 has no video i/o,may be I can buy extra box so kids' game can be hooked.