Lenovo ThinkVision LT1421 Review

Laptop Mag Verdict

The best portable monitor on the market, the ThinkVision LT1421 offers wide viewing angles, light weight, and great performance over a single USB connection.


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    Runs on USB power

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    Bright screen with wide viewing angles

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    Lightest product in its class

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    Attractive ThinkPad-inspired design


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    Bulky cover

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    Weaker Mac performance

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It's no secret that using multiple monitors dramatically increases your productivity at the home or office, but the moment you travel with your laptop, you're stuck with a single screen. This year, we've seen a couple of vendors rise to the challenge by releasing portable USB monitors that can fit right in your notebook bag. Lenovo's 14-inch ThinkVision T1421 ($199) is clearly the best of these portable displays, with wide viewing angles, great image quality, and the ability to transfer power and data over a single USB connection.


If you like the traditional ThinkPad aesthetic Lenovo uses on its business notebooks, you'll love the look of the ThinkVision LT1421. The 13.2 x 8.6 x 0.85-inch LT1421 has a raven-black chassis with a thin bezel and a mostly flat back that has a tiny box which contains a microUSB port, a brightness rocker, and a bendable arm that you can use to prop up the monitor and adjust its angle. The thick plastic arm carries a bright red accent and has a durable feel, which makes us believe it will stand up to regular travel.

A thin black cover (which looks a ThinkPad lid) snaps onto the front of the LT1421 to protect the screen from scratches and nicks while it rides in your bag.

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When the cover's detached, you can place the ThinkVision LT1421 on top of it and use it as a base, though the monitor stands up just fine when placed directly onto a flat surface.

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Unfortunately, the cover is a little difficult to pop on and off of the screen, and we found ourselves struggling with it on a few occasions. It also adds 0.6 pounds to the weight of the otherwise 1.8-pound monitor.

At 2.4 pounds with the cover attached, the LT1421 is significantly lighter than the Toshiba USB Mobile Monitor, which is 2.8 pounds without its AC adapter and 3.4 pounds with it. It's also less than half the weight of the 15-inch Field Monitor Pro, which weighs a whopping 5 pounds with its AC adapter.

USB Connectivity

Where the Field Montor Pro requires an AC adapter to work at all and the Toshiba USB Mobile Monitor runs at painfully low brightness without its wall wart, the ThinkVision LT1421 is completely bus-powered. The portable Lenovo display comes with a Y cable that has a single microUSB port on one end for plugging into the monitor and two full-size USB plugs on the other end for attaching to your notebook.

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A Lenovo rep told us that the second of the dual plugs is only needed if you have an older notebook which doesn't supply adequate power through one USB port. In tests on both a ThinkPad X301 and a MacBook Pro, we only needed to use the right plug to get full power and data to the monitor.

Lenovo says you can attach up to six ThinkVision LT1421 monitors to a single PC, which is standard for all monitors that use the same DisplayLink USB video technology that powers this monitor. The LT1421 doesn't have a pass-through, so you'll need to attach any additional monitors to their own USB ports or use a hub.

Installation and Compatibility

When you plug the ThinkVision LT1421 into a Windows notebook for the first time, you will need to install its drivers manually. At least in our tests, Windows 7 was unable to find and download them on its own. Lenovo bundles the LT1421 with an install CD, but if you don't have an optical drive, you will have to download the driver directly from Lenovo.com.

Lenovo doesn't burden you with an unnecessary control panel application, because there isn't much to control. Windows 7's built-in display control panel allows you to set whether the monitor is used in mirror or extended mode. You can raise and lower screen brightness with the rocker on the back of the monitor. There's no power button so you need to simply pull its USB cord out when you want to turn off the LT1421.

Though Lenovo doesn't offer drivers for platforms other than Windows, DisplayLink--the company which makes the controller inside the ThinkVision LT1421--has compatible software for Mac available on its site. After installing version 1.6 of the DisplayLink USB driver on a 2011 MacBook Pro, we were able to attach the LT1421 without a problem.

Image Quality

We were pleased by the bright, colorful images we saw on the ThinkVision LT1421's 14.1-inch, 1366 x 768 screen. The 200-nit matte display offers similar image quality to a high-quality notebook screen. Because of the matte coating, viewing angles were extremely wide; the picture remained bright even at angles greater than 45 degrees to the left and right. We did find that the image quality degraded when the screen was tilted too far back, so you'll want to adjust the arm to get the right vertical angle.

When we attached theLT1421 to our ThinkPad X301, we were able to play back both 720p YouTube videos and a 1080p MP4 file without any jerkiness or loss of quality. Considering that the X301 notebook uses an old 1.4-GHz Core 2 Duo CPU with integrated graphics, we were impressed. We also didn't notice a difference in CPU utilization between playing the movie on the notebook's screen (with no monitor attached) and on the Lenovo screen.

When we attached the ThinkVision LT1421 to a 2011 MacBook Pro and tried playing the same 1080p MP4 file we had run on the ThinkPad, we experienced noticeable jerkiness that went away the moment we dragged our video window back to the laptop's main screen. Considering that the Mac uses a different driver on its operating system, this could be a software issue.


The ThinkVision LT1421 is a must-have accessory for anyone who wants to maximize productivity when working from the road. With a portable second screen, you can easily compare documents, view research in one screen while creating content in another, watch a movie while working, or keep a constantly updating application such as e-mail or TweetDeck visible at all times. You can even employ the monitor as a sales tool and show a presentation to someone sitting across from you.

Competitive products don't match the ThinkVision LT1421's lightweight design and ability to achieve strong picture quality over USB bus power alone. This is the portable monitor to buy.

Lenovo ThinkVision LT1421 Specs

Accessories TypeMonitor
Company Websitewww.lenovo.com
SizeThe 13.2 x 8.6 x .85 inches
Weight2.4 pounds with cover, 1.8 without
Avram Piltch
Online Editorial Director
The official Geeks Geek, as his weekly column is titled, Avram Piltch has guided the editorial and production of Laptopmag.com since 2007. With his technical knowledge and passion for testing, Avram programmed several of LAPTOP's real-world benchmarks, including the LAPTOP Battery Test. He holds a master's degree in English from NYU.