Questions about a dock for the X220

[catback]

Hi,

I'm looking for a dock to use with my X220 that will let me connect an external monitor and keyboard/mouse. A CD drive integral with the dock is a plus but not necessary. I have a few questions I hope some of you can clarify.

Looking on ebay, there seems to be a few variety of docks available. I noticed some of these have a square section that extends out in the upper left corner. What exactly is this section?

Do all the docks compatible with the X220 have a power button that lets you turn on the laptop without having to open the laptop lid and use the laptop's power button?

I see docks referred to as an UltraBase, MiniDock and replicator. Are these all essentially the same dock?

[dr_st]

There are actually many docks that support the X220.

All of these (which are also supported by the larger T/W/L series):
http://www.thinkwiki.org/wiki/ThinkPad_Dock_Series_3

And the Ultrabase, which is specific to the X220:
http://www.thinkwiki.org/wiki/ThinkPad_ ... e_Series_3

All of them support external keyboard, mouse, monitor. All of them have the power button and can be locked.

Only the Ultrabase has the CD/DVD drive.

The Ultrabase is designed to be slightly more mobile, so that in theory you can carry it attached to your laptop (although most people still wouldn't).