Lenovo ThinkPad T420s Review

Laptop Mag Verdict

The ThinkPad T420s combines speedy performance, a great keyboard, and a hi-res screen in the lightest 14-inch laptop money can buy.


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    Lightweight and durable design

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    Hi-res screen

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    Strong performance

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    Great keyboard


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    Modest battery life

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    Mediocre sound

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Lenovo's ThinkPad T420s is the business user's ultimate Goldilocks notebook. At 14.1 inches and 4 pounds, the laptop is extremely light and portable, but it's large enough to provide a generous high-res screen, a powerful processor, and a full-sized keyboard and touchpad. However, with a price of $1,349 (as configured), the ThinkPad T420s costs more than heavier 14-inch systems such as the ThinkPad T420 and the HP EliteBook 8460p. Spoiler alert: This lightweight notebook is worth the investment.


From its raven-black soft-touch lid to its strong chrome hinges and elegantly simple black interior, the Lenovo ThinkPad T420s has traditional ThinkPad styling right down to the bright red track point in the middle of its keyboard. Though the system offers few a new riffs on this tried-and-true theme, users will appreciate the clean bottom and sleek sides on the T420s, as well as its large, textured touchpad and dedicated volume and microphone buttons that sit above the keyboard.

At 13.5 x 9.1 x 0.8-1 inches and 4 pounds, the ThinkPad T420s is significantly thinner and lighter than competitors such as the HP Elitebook 8460p (1.3 inches thick 5.4 pounds) and Dell Latitude E6420 (1.3-inch profile, 6.2 pounds with a nine-cell battery). The Toshiba Tecra R840 is just as thin, but it weighs a heavier 4.6 pounds. The ThinkPad T420s is just a tad wider and taller than the previous generation ThinkPad T410s, because Lenovo chose to switch to a wider 16 x 9 screen from the older 16 x 10 standard.

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Klutzes will appreciate the durable ABS plastic lid and carbon fiber-reinforced bottom on the T420s. An internal roll cage protects the internal components in the event of a fall. The keyboard has a drainage system that routes spilled liquids out through two drainage holes in the bottom.

Keyboard and Touchpad

The Lenovo ThinkPad T420s uses the same, classic-style keyboard we've come to know and love on many other ThinkPads. With a complete set of legacy keys--including the ancient pause and scroll lock keys--and enlarged Esc and Del keys, the T420s keyboard offers a superior typing experience with strong tactile feedback and smile-shaped keys that make it easy to avoid mistypes.

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The T420s's long palm rest also provides more than enough room to support adult-sized wrists. The combination of these factors led us to a score of 86 words per minute on the Ten Thumbs Typing test, slightly above our 80-wpm average.

We've long been fans of Lenovo's TrackPoint pointing stick, and the red nub on the ThinkPad T420s continues this proud tradition by offering extremely accurate navigation. The 3.2 x 2-inch textured touchpad was also highly accurate, but multitouch gestures such as pinch-to-zoom were not smooth. The two discrete mouse buttons offer just the right amount of feedback.


Thanks in part to its dual exhaust ports, the ThinkPad T420s stayed cool during our use. After steaming a video at full screen for 15 minutes, we measured the touchpad at a chilly 84 degrees, the keyboard at a mere 90 degrees, and the bottom at only 91 degrees. We consider temperatures below 95 degrees comfortable.

Display and Audio

The 1600 x 900, matte 14.1-inch display on the T420s offers sharp images and significantly more desktop real estate than the 1366 x 768 panels we see on most other notebooks this size. The difference between 768 and 900 pixels of vertical space is a significant advantage because it can show you several additional lines of text on your favorite web pages, e-mails, and docs without requiring you to scroll.

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At 250 nits and with a 300:1 contrast ratio, the ThinkPad T420s's screen isn't especially bright or colorful, but its antiglare surface allows for reasonable viewing angles. We were able to get a decent, though slightly white-washed, view of the desktop at up to 90 degrees to the left or right, but videos got totally washed out at angles greater than 45 degrees.

Though the ThinkPad T420s's speakers are accurate enough for conferencing and playing movies, they sounded somewhat tinny during music playback. The bundled Dobly Home Theater v4 software didn't help much. Disabling this enhancement tech led to louder volumes but even harsher audio.

Ports and Webcam

The ThinkPad T420s has a Kensington lock slot and a Wi-fi on/off switch on the right side. On the back are an Ethernet port, VGA, Display Port out, and two USB ports. The first is a yellow USB port for charging gadgets while the notebook sleeps and a light blue one for connecting super-speed USB 3.0 devices. A memory card reader, headset jack, and a third USB port line the left side.

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The 720p webcam captured sharp, accurate images even in low light. When we were chatting on Skype in a room with overhead fluorescent lighting, our call partner reported that fine details of our face were visible, though a little overly bright. When shooting pics in our shadowy office cubicle, our face was a little darker but still sharp, though we got the best color quality when we sat in front of a window on a sunny day.

Click to enlargeLenovo's dual array microphone provides excellent audio capture for conferencing on the T420s. We particularly like the keyboard noise-suppression filter. When the filter was on, our call partner said she could barely detect the sound of our keystrokes as we typed.


The combination of a 2.5-GHz 2nd Generation Intel Core i5 CPU, Intel HD 3000 graphics, and a 320GB, 7,200-rpm hard drive give the ThinkPad T420s strong performance that's good enough for any task. On PCMark Vantage, which measures overall performance, the T420s scored a strong 7,169, which is well above the 5,584 thin-and-light notebook average. This score also beats the Core i5-powered HP Elitebook 8460p (6,449), but it falls short of the Dell Latitude E6420 (Core i5-2540M; 8,242).

The 320GB, 7,200-rpm hard drive booted Windows 7 Professional (64-bit) in a reasonable 60 seconds, just 5 seconds quicker than the category average. The drive took 3 minutes and 9 seconds to complete the LAPTOP File Transfer test, which involves copying 4.97GB of mixed-media files. That's a rate of 26.9 MBps, just above the category average of 25.7 Mbps.

When it came to video editing, the ThinkPad T420s was no slouch, taking just 42 seconds to convert 114MB MP4 to AVI format using Oxelon Media Encoder. That's 16 seconds quicker than the category average, but about on par with the EliteBook 8460p (0:42), the Dell Latitude E6420 (0:40), and the Toshiba Tecra R840 (0:41).


The integrated Intel HD 3000 Graphics chip on the ThinkPad T420s is more than powerful enough to play high-def video. Both a full HD Flash trailer of Cowboys and Aliens and a 1080p QuickTime trailer of Captain America were smooth and sharp. On 3DMark06, which measures overall graphics prowess, the T420s scored a respectable 3714, about on par with the category average but way behind the discrete GPUs on the Dell Latitude E6420 (5,060) and the Toshiba Tecra R840 (4,369).

You can order the T420s with Nvidia NVS 4200M discrete graphics if you opt for the model that starts at $1,274; when the notebook is similarly configured to our system, the premium for the GPU is $107.

When playing World of Warcraft, the ThinkPad T420s' integrated graphics achieved a barely playable framerate of 24 fps. However, when we turned the special effects up, that rate dropped to an unplayable 11 fps.

Battery life and Wi-Fi

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The ThinkPad T420s lasted exactly 5 hours on the LAPTOP Battery test, which involves continuous web surfing over Wi-Fi. That's an exact match with the thin-and-light notebook category average and way ahead of last year's ThinkPad T410s ,which lasted only 3 hours and 47 minutes on a charge. However, the Dell Latitude E6420 with a nine-cell battery lasted 4 hours longer (8:59), as did the HP Elitebook 8460p (6:01) and the Toshiba Tecra R840 (6:34). Fortunately, Lenovo sells a three-cell bay battery ($119) that can be swapped with the optical drive to provide extra juice.

The ThinkPage 802.11 b/g/n wireless card provided reasonable transfer rates of 35.7 and 20.9 Mbps at distances of 15 and 50 feet from our router. Those numbers are about on par with the category averages of 35.4 and 21.7 Mbps.

Configuration Options

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Our review configuration of the ThinkPad T420s carries an MSRP of $1,399. For that price, you get a 2.5-GHz Core i5-2520M CPU, 4GB of RAM, a 320GB hard drive, and Windows 7 Professional. For a starting price of $1,249, you get the same processor and hard drive, but just 2GB of RAM and Windows 7 Home Premium instead of Professional and no webcam.

You can configure the T420s with up to a 2.7-GHz Core i7-2620M CPU, with Nvidia NVS 4200M discrete graphics, up to 8GB of RAM, and with a 128GB or 160GB SSD instead of the 7,200-rpm hard drive. We recommend that you splurge for the ultrabay battery ($119), which should provide an additional 2 or 3 hours of endurance. Security conscious users will want to pay $20 extra for the fingerprint reader.

Software and Warranty

Lenovo bundles the ThinkPad T420s with its standard array of ThinkVantage utilities. Our favorite of these is the ThinkVantage Power manager, which allows you to exert fine control over power consumption. The Power Manager even has a unique feature called Instant Resume, which will keep your Wi-Fi card active for the first 10 minutes after the notebook goes to sleep so. If you wake the laptop again during that time window, you won't have to wait for the system to reconnect.

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Other utilities include a Password Manager, Access Connections for controlling your wireless connections, and Rescue and Recovery for backups. The system also has Corel Burn Now for authoring discs and Corel WinDVD SD for playing movies.

Click to enlargeLenovo backs the ThinkPad T420s with a standard one year warranty on parts and labor. See how Lenovo did on our latest Best & Worst Brands feature and our annual Tech Support Showdown


The lightest 14-inch notebook on the market, the Lenovo ThinkPad T420s remains a truly compelling choice for business users looking for the optimum combination of power and portability. The HP EliteBook 8460p has a more attractive design, and the Dell Latitude E6420 offers longer battery life. But if you want the best keyboard, a high-res screen, and solid performance, this is the business laptop to beat.

Lenovo ThinkPad T420s Specs

CPU2.5-GHz Intel Core i5-2520M
Card SlotsSD memory reader
Company Websitehttp://www.lenovo.com
Display Size14.1
Graphics CardIntel HD Graphics 3000
Hard Drive Size320GB
Hard Drive Speed7,200rpm
Hard Drive TypeSATA Hard Drive
Native Resolution1600x900
Operating SystemWindows 7 Professional (64-bit)
Optical DriveDVD+/-RW DL
Optical Drive Speed8X
Ports (excluding USB)VGA, USB 3.0, Ethernet, DisplayPort
RAM Upgradable to4GB
Size13.5 x 9.1 x 0.8-1-inches
Touchpad Size3.25 x 2 inches
USB Ports3
Video Memory64MB
Warranty/SupportOne year standard parts and labor
Weight4 pounds
Wi-Fi802.11 a/g/n
Wi-Fi ModelThinkpad b/g/n wireless
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.