Lenovo ThinkPad T420s

  • Editors' rating
    8.0 Excellent
  • $2,399.00


  • Traditional design with solid build quality
  • Best-in-class keyboard
  • Matte 16:9 screen
  • Hybrid discrete/integrated graphics
  • Fast solid-state drive
  • High-quality webcam, mic and speakers
  • Integrated mobile broadband
  • Configurable specification


  • Expensive
  • Disappointing battery life

Lenovo's T-series ThinkPads are designed to offer mobile professionals an appealing combination of performance and portability, wrapped up in the familiar durable ThinkPad design. The slimline 14in. T420s features Sandy Bridge processors and optional dual-mode integrated/discrete graphics, along with additions (under the banner Enhanced Experience 2.0 for Windows 7) such as rapid boot-up and shutdown. As with all ThinkPads, there's also a veritable arsenal of ThinkVantage Tools that help to keep the system secure and up-to-date.

The black-clad T420s looks every inch a ThinkPad, its standout visual features being the 14in. 1,600-by-900-pixel screen (which is LED-backlit and pleasingly non-glossy) and the traditional (non-isolation-style) keyboard.

The ThinkPad T420s is a 14in. notebook for business users with traditional tastes

The T420s is also noticeably slim for a full-featured business notebook at just 2.1-2.59cm, while the footprint, at 34cm wide by 23cm deep, means it should fit comfortably into most laptop bags. Sturdy construction and a solid two-point screen clasp should keep safe and sound in transit.

There's little flex in the lid section, and the keyboard feels admirably firm when you're typing. The system weighs a very manageable 1.78kg with an optical drive in the modular bay (as in our review unit), and the 90W power brick is reasonably compact.

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We've used plenty of 'modern', MacBook-imitating isolation-style keyboards, and some (including those on Lenovo's own ThinkPad Edge series) are perfectly usable. But given the choice, we'd select the traditional ThinkPad keyboard, as seen on the T420s, every time. In terms of feel and layout, it simply cannot be beaten, in our opinion. There's no backlight, but you do get the Fn+PgUp-toggled ThinkLight that shines down from the top of the lid to help you work in dimly-lit conditions.

No 'chiclet' keys here, just nicely sculpted contiguous keys with plenty of travel on a rock-solid base

We've also used plenty of pointing sticks from other vendors, but few compare to those from its inventor. You get three buttons with the trackpoint (right and left mouse, plus scroll), and two with the stipple-surfaced touchpad, which has built-in vertical and horizontal scroll zones. The wrist-rest area has a fingerprint reader on the right-hand side, above the ThinkPad logo.

Our review sample of the ThinkPad T420s was powered by Intel's quad-core Core i7-2640M processor running at 2.8GHz (3.5GHz with Turbo Boost), supported by 4GB of DDR3 RAM. Up to 8GB of memory is supported, by filling both DIMM slots with 4GB RAM modules. A more affordable Core i5-2520M-based system is also available on Lenovo's UK web site, and you can customise the detailed configuration of both models.

The review unit was equipped with both discrete and integrated graphics, in the shape of Nvidia's NVS 4200M GPU with 1GB of dedicated DDR3 video memory and Intel's CPU-integrated HD Graphics 3000, which can dynamically command between 64MB and 1,696MB of system memory for its purposes. The NVS 4200M supports Nvidia's Optimus technology, which automatically switches between discrete and integrated graphics according to the workload, maximising battery life by not using a high-power GPU for low-end tasks.

Storage comes in the form of a fast, low-power 160GB Intel solid-state drive (SSD). This is an expensive option, and you can specify lower-capacity 128GB SSD for £79.80 (ex. VAT) less, or a 320GB, 7,200rpm hard drive for £214.12 (ex. VAT) less.

Connectivity options are excellent, our review sample not only featuring dual-band Wi-Fi (802.11a/b/g/n) and Bluetooth (3.0), but also HSPA mobile broadband (Ericsson F5521gw). Among the ThinkVantage Tools you'll find a Mobile Broadband Activate utility to set the connection when you insert your SIM. There's Gigabit Ethernet for wired networking too, of course.

You get a reasonable selection of ports and connectors on the T420s, but many users will want to add a port replicator or a docking station for extra features and in-office convenience.

The left-hand side has a USB 2.0 port and a 34mm ExpressCard slot, while the right-hand side is taken up mostly by a modular Ultrabay, fitted with an optical drive in our review unit. If you want the full claimed 10-hour battery life, you can replace the optical drive with a second 3-cell Ultrabay for an extra £68.40 (inc. VAT) to complement the system's primary 6-cell battery.

At the back, from left to right, there's an RJ-45 (Ethernet) port, a USB 3.0 port, a sleep-and-charge USB 2.0 port, a DisplayPort and a 15-pin VGA port.

If you want to keep network and external monitor connections in place in the office, a ThinkPad Port Replicator Series 3 with Ethernet, four USB 2.0 ports and a VGA connector will cost you £107.35 (ex. VAT) extra. A Mini Dock Series 3 with Ethernet, six USB 2.0 ports, VGA, DVI and DisplayPort connectors, plus a pair of audio jacks costs £178.60 (ex. VAT).

Other noteworthy features include a 720p HD webcam and a dual array microphone in the top screen bezel, and a pair of stereo speakers flanking the keyboard. These can be configured using the Communications Utility in ThinkVantage Tools, which includes useful settings such as microphone optimisation for single or multiple voices, keyboard noise suppression and single or multiple audio streams (over speakers and headphones).

Performance & battery life
Lenovo sets great store by the speed with which the ThinkPad T420s boots into Windows 7, claiming this can be achieved "in as fast as 10 seconds". Our review sample didn't show such eagerness to get Windows going, but booted up in a perfectly acceptable 30 seconds on average. It was quicker to exit Microsoft's OS though, taking just under 10 seconds to shut down.

WEI (Windows Experience Index) scores for the ThinkPad T420s ranged between a middling 4.7 (out of 7.9) for Graphics (Desktop performance for Windows Aero) and an impressive 7.5 for Primary hard disk (Disk data transfer rate). In between came Memory (RAM) (Memory operations per second) with 5.9, Gaming Graphics (3D business and gaming graphics performance) with 6.2 and Processor (Calculations per second) with 7.1.

Although the graphics subsystem delivers relatively low WEI scores compared to those for processor and primary hard disk (SSD in this case), bear in mind that the relatively undemanding WEI tests will be hitting the integrated Intel HD Graphics 3000 rather than the discrete Nvidia NVS 4200M GPU, which will kick in under Optimus when the graphical going gets tougher. In two weeks of general 'knowledge worker' use, we found the T420s admirably responsive.

Lenovo claims "up to 10 hours" of battery life for the ThinkPad T420s, when equipped with the primary 6-cell Li-ion battery and a second 3-cell Ultrabay battery. We didn't have the latter, which is a £57 (ex. VAT) option. To test the system's longevity with just the primary battery, we measured the system's average power consumption under idle and workload conditions, using a Voltcraft VC940 Plus multimeter. Dividing the resulting figures into the 6-cell battery's 44Wh capacity gives us estimates for battery life.

We tested the power consumption of the T420s under the Maximum Performance and Maximum Battery Life power plans, both idling at the Windows 7 desktop and performing a demanding workload (Cinebench 11.5's CPU test). Our battery life estimates ranged between 3 hours 19 minutes and 51 minutes, suggesting that Lenovo's battery life claims are optimistic and that you'll need that additional Ultrabay battery to get anything approaching a day's work from this notebook without a power socket to hand.

Much of the ThinkPad's design — and particularly the excellent keyboard — is traditional, but it packs plenty of up-to-date specs too: Core i7 CPU, hybrid discrete/integrated graphics, solid-state drive, USB 3.0 and a high-quality multimedia subsystem. All this makes for an expensive notebook, but it's one we're happy to recommend.


Packaged Quantity 1
Platform Technology Intel vPro Technology
Built-in Devices ThinkLight
Embedded Security Trusted Platform Module (TPM 1.2) Security Chip
Notebook type HD display, Midsize
Processor / Chipset
CPU Intel Core i5 (2nd Gen) 2520M / 2.5 GHz
Max Turbo Speed 3.2 GHz
Number of Cores Dual-Core
Cache L3 - 3 MB
64-bit Computing Yes
Chipset Type Mobile Intel QM67 Express
Features Hyper-Threading Technology, Intel Turbo Boost Technology 2.0, integrated memory controller
Cache Memory
Type L3 cache
Installed Size 3 MB
Memory Speed 1333 MHz
Memory Specification Compliance PC3-10600
Configuration Features 1 x 4 GB
Technology DDR3 SDRAM
Installed Size 4 GB
Rated Memory Speed 1333 MHz
RAM 4 GB (1 x 4 GB)
Max Supported Size 8 GB
Technology DDR3 SDRAM
Speed 1333 MHz / PC3-10600
Form Factor SO-DIMM 204-pin
Slots Qty 2
Empty Slots 1
Interface Serial ATA-300
Optical Drive DVD-Writer removable
LCD Backlight Technology LED backlight
Widescreen Display Yes
Image Aspect Ratio 16:9
Monitor Features anti-glare
Type LED
Diagonal Size (metric) 35.5 cm
Display Resolution Abbreviation HD+
Hard Drive
Type SSD
Capacity 128 GB
Audio & Video
Graphics Processor Intel HD Graphics 3000
Memory Allocation Technology Dynamic Video Memory Technology
Integrated Webcam Yes
Capture Resolutions 1280 x 720
Sound Stereo speakers, stereo microphone
Audio Codec CX20672
Type TrackPoint, UltraNav, keyboard
Features multi-touch touchpad, spill-resistant
Wireless Protocol 802.11a/b/g/n, Bluetooth 3.0
Wireless Controller Intel Centrino Advanced-N 6205
Wired Protocol Gigabit Ethernet
Wireless Broadband (WWAN)
Generation 3G upgradable
Optical Storage
Drive Type DVD-Writer
Type DVD-Writer
Form Factor removable
CPU Type 2nd Gen Core i5
Processor Number i5-2520M
Generation 2
Manufacturer Intel
Clock Speed 2.5 GHz
Cells 6-cell
Technology lithium ion
Run Time (Up To) 5.5 hour(s)
Card Reader
Type 4 in 1 card reader
Supported Flash Memory MultiMediaCard, SD Memory Card, SDHC Memory Card, SDXC Memory Card
AC Adapter
Input AC 120/230 V (50/60 Hz)
Output 65 Watt
Connections & Expansion
Expansion Bays 1 x Ultrabay Slim
Slots 1 x ExpressCard/34 (1 free)
Interfaces USB 2.0
Headphone/microphone combo jack
USB 3.0
Memory Card Reader 4 in 1 (SD Card, MultiMediaCard, SDHC Card, SDXC Card)
Brand Lenovo
Product Line Lenovo ThinkPad T420s
Model 4174
Localization English
Packaged Quantity 1
Compatibility PC
Platform Technology Intel vPro Technology
Notebook Type notebook
Platform Windows
Hard Drive Capacity 128 GB
Embedded Security Trusted Platform Module (TPM 1.2) Security Chip
Microsoft Office Preloaded Includes a pre-loaded image of select Microsoft Office 2010 suites. Purchase an Office 2010 Product Key Card or disc to activate preloaded software on this PC.
Diagonal Size 14 in
Data Link Protocol Bluetooth 3.0, Ethernet, Fast Ethernet, Gigabit Ethernet, IEEE 802.11a, IEEE 802.11b, IEEE 802.11g, IEEE 802.11n
Wireless LAN Supported Yes
Wireless NIC Intel Centrino Advanced-N 6205
Integrated Options ThinkLight
Security Trusted Platform Module (TPM 1.2) Security Chip
Features Intel Active Management Technology (iAMT), ThinkPad Roll Cage, administrator password, hard drive password, power-on password
Included Laptop Accessories power adapter
Compliant Standards RoHS
Manufacturer Selling Program Global Models Plus
Theft/Intrusion Protection security lock slot (cable lock sold separately)
Security Slot Type Kensington security slot
Dimensions & Weight
Width 13.5 in
Depth 9.1 in
Height 1 in
Audio Output
Compliant Standards High Definition Audio
Manufacturer Warranty
Type 3 years warranty
Chipset Type Mobile Intel QM67 Express
Environmental Standards
ENERGY STAR Certified Yes
Physical Characteristics
Weight 3.75 lbs
Operating System / Software
OS Provided: Type Microsoft Windows 7 Professional 64-bit Edition
Type Adobe Reader, Corel Burn.Now Lenovo Edition, Corel DVD MovieFactory Lenovo Edition, Corel WinDVD, Norton Internet Security 2010 (30 days subscription), Skype, ThinkVantage Access Connections, ThinkVantage Power Manager, ThinkVantage Rescue and Recovery, ThinkVantage System Update, ThinkVantage Toolbox, Windows Live Essentials
Video Output
Graphics Processor Intel HD Graphics 3000
Graphics Processor Series Intel HD Graphics
Video Memory
Memory Allocation Technology Dynamic Video Memory Technology
Notebook Camera
Integrated Webcam Yes
Expansion Bays
Total Qty 1
Service & Support
Type 3 years warranty
Service & Support Details
Type limited warranty
Service Included parts and labor
Location on-site
Full Contract Period 1 year, 3 years
Response Time next business day
Service Availability (Hours a Day) 9 hours a day
Service Availability (Days a Week) Monday-Friday
Greenpeace policy rating (Nov 2011) 3.8