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Question: Is there just the one usb 3.0 on the mini dock? I have two external hard drives, both usb 3.0.
Document: The dock works well. One note - it took me 5 minutes of frantic searching before realizing the AUDIO-OUT mini-RCA jacks are on the right side and underneath the docked laptop. Don't look for it on the back panel.USB 3.0 is great for external HD - backups go fast.
The mini dock is the very best way to enjoy the portability of a notebook that has to work in more than one room. The ease of just dropping the notebook on the mini dock and having all your accessories already connected is priceless. This one supports two external monitors and it does work. Only three stars because Lenovo doesn't believe in putting HDMI ports on its mini docks. I had to buy adapter cords from Amazon to get things connected.
Hi AllThis is a docking station. Nothing glorious or glamorous - tho' the USB 3.0 port provides a near-out-of-body-experience!BUT:  When you have external speakers attached (using the Mini Dock's audio-out jack), you get an almighty "kah-lick" every time there is a change in the audio output (i.e. when it goes from quiet to a voice, or a song starts, or the volume is adjusted, or pretty mauch anything!
I must plug my HDD into the USB 3.0 port on the side of my laptop to get the proper USB 3.0 connection. I will be very unhappy if it's a true  rumor that the docking station's USB 3.0 will only work with Lenovo brand external drives.Are these flaws or operator error? I am just not technical enough to know, and was foolish to have assumed there would be a user's manual in the box or online. I have used the Displayport with no issues.
Neither the power button on the docking station, nor the power button on my W520 keyboard will work. I must release the W520 from the docking station to power on, then place my W520 back into the docking station.The next problem is that the USB 3.0 port on the docking station will not function as USB 3.0 with my external HDD (a 3T "Seagate Desktop Plus" USB 3.0 device).
I'm sure in a couple of years the price will come down considerably but you do pay a lot for that one USB 3.0 port.
The main issue here is that the attach and unattachment of the PC wokrs flawlassly. It connects easily and disconnects easily. The main purpose of the dock is to allow you to have your monitor and all your gadgets plugged into the dock. Then you can dock and undock quickly. This is important if you do not want to plug and unplug all your stuff from your PC two or three times a day. The extra slots to plug all your gadgets into work very well. the USB 3 works as advertised.
I like docking stations because this gives me more ports, extra monitors, etc. without having to set things up every time. I have one at home and one at work. My only complaint is that the charger of this thing (170W) is as big as a brick. It's hard to store behind a desk because of the size.
I have a ThinkPad 520W. It is powerful enough to replace my desktop. But the 15" screen is just not enough.With the MiniDock, i have been able to add two 24" external monitors along with the laptop display. I now have three work surfaces. I tend to keep a dozen windows open at once, so three screens is a great feature.
The mini dock is an excellent way of shaving minutes at work. I used to spend the first moments at the office plugging my w520 laptop to all the peripherals, now it's just a drop on the dock! It could use an attachment system to the desk though.
Answer: Yes