IBM ThinkPad X31

  • Editors' rating
    8.0 Excellent
  • $2,079.00


  • Long battery life
  • light weight
  • bright screen
  • versatile design
  • built-in wireless networking and hardware encryption.


  • Relatively slow application performance
  • poor graphics performance.

How long before the electronics industry makes a major breakthrough in battery power? In the meantime, power-conserving computer chips can do more with less -- at least if Intel's Pentium M is any indication. The low-power processor shows up in IBM's ThinkPad X31 and delivers impressive working time in an ultra-lightweight system. The X31 that we looked at was configured as a true-blue Centrino, although you can also specify IBM's 802.11a/b wireless and built-in Bluetooth. Beyond its 3.5-hour battery life (6 hours with a second battery fitted), the X31 offers flawless design and flexible configurations. The ThinkPad X31 makes a desirable package for someone who travels a lot and relies on long-running batteries.

IBM's painstaking industrial design makes the ThinkPad X31 a pleasure to use. Its case is made of a sober-looking, matte-black plastic, with the company's signature lip extending from the closed lid's edges to seal around the base. For a notebook with no floppy or optical drive, the X31 is on the big side, at 27.3cm wide, 22.3cm deep and 3.02cm high. Despite these dimensions, though, it weighs just 1.66kg (2.04kg with the power cord and the AC adapter). That's comparable to other ultraportables, despite the X31's relatively large proportions. For £142 (ex. VAT), you can attach a snap-on dock called the X3 UltraBase, which adds stereo speakers, a battery charger on the bottom and a swappable bay (a combo DVD/CD-RW drive for that bay costs £223 ex. VAT). With the dock, the X31 can actually have three batteries installed at the same time: the notebook's main battery, another main battery in the dock, and a battery in the dock's drive bay. The UltraBase adds 2.5cm to the X31's thickness and (with a DVD/CD-RW combo drive fitted in the modular bay) 880g to its heft, so if you're travelling, just toss the dock in your suitcase and plug in an external battery to the dock connector, and you'll still have a spare. The X30 Series Extended Life Battery costs £140 (ex. VAT) and adds 420g to the system weight. The dock and the notebook co-operate well. To separate them while the system is running, push the blue button on the dock's front edge and wait for an on-screen message; then pull the lever on the left side, and the notebook pops up. To reconnect them, just slide the notebook toward yourself along the face of the dock, and it flops into place. The dock can come in handy for charging the notebook's main battery when you leave it in your hotel room. Unfortunately, only the notebook itself can charge the external battery. Two catches hold the X31's lid snugly closed. And when you open the lid, thick steel hinges keep it right where you position it. The lid folds all the way back, so you can stand up at a desk or a podium and look straight down onto the 12.1in. (diagonal) screen. The keyboard clatters when you type, but it feels extremely tight and responsive. The keys are surprisingly big, with no wiggle whatsoever, and the keyboard doesn't sag a bit. Instead of a touchpad, the X31 has a pointing stick embedded between the G, H and B keys. Pointing sticks can be irritating because they're hard to steer without typing in a random G or H, but this one comes with a mushroom-shaped tip to prevent that. IBM packs the X31 with the original eraserhead tip and a new shape as well, but we think that the mushroom tip will be a big success.

We're not joking when we say that the ThinkPad X31 is packed with features. The left edge sports a USB 2.0 port, a Type II CompactFlash slot, a Type II PC Card slot, a rare FireWire port and an infrared port. The back edge offers parallel and monitor ports, another USB 2.0 port, plus an 10/100 Ethernet port and a modem port. The dock adds a PS/2 port for an external mouse and a serial port for syncing your PalmPilot. The notebook lid conceals wireless network antennae for Bluetooth and Wi-Fi, although our review sample only had Intel's PRO/Wireless LAN 2100 Wi-Fi Mini-PCI card fitted. IBM also builds in its Embedded Security Subsytem 2.0 -- a processor that authenticates notebook users and encrypts wireless and wired communication -- as standard equipment. Under the surface, the X31 features a comfortably large 40GB hard drive but only 256MB of PC2100 DDR memory, although you can bump up the memory to 512MB. The X31 takes either a 1.3GHz or a 1.4GHz Pentium M processor, making it fast enough for basic productivity tasks (although not as speedy as competing Pentium M systems that feature 1.5GHz or even 1.6GHz processors). Our performance tests bear out that performance hit. The X31's standalone ATI Mobility Radeon graphics controller, with just 16MB of its own memory, produced bright, saturated colours and good focus on a 1,024 by 768 screen, but it's not a great performer.

Performance & battery life
The ThinkPad X31 is the first sub-2kg ultraportable Pentium M system we've tested -- the previous machines were either desktop replacements or thin-and-lights. At 1.4GHz, its processor is also among the slowest we've seen -- only the thin and light ThinkPad T40 is slower at 1.3GHz. Mainstream application performance, as measured by Business Winstone 2001, is adequate but by no means impressive – the X31's score of 43 is actually beaten by the 1.3GHz T40, which returned 48.7 in this test. Similarly, although the X31 runs high-end applications happily enough, a Content Creation Winstone 2002 score of 27.4 is the lowest we've recorded so far for a Pentium M system. As mentioned above, the X31's 16MB Mobility Radeon graphics controller isn't a great performer, particularly when it comes to 3D acceleration. A score of 1,460 under 3DMark 2001 doesn't come close to the leading edge for Pentium M systems, so don't look to the X31 for good gaming performance. The ThinkPad X31 continues the Pentium M tradition of very good battery life. The system lasted 3 hours and 34 minutes under BatteryMark 4.01, which is impressive considering that our review sample had a 10.8V, 4,400mAh battery -- not the most highly specified unit. With the extended life battery fitted as well, the X31 delivered 6 hours and 3 minutes. Throw in a few power management tweaks, and you'll easily get a full day's work from the X31 on two batteries.

Service & support
IBM provides three years of warranty coverage that includes prepaid shipping and free telephone support. IBM also markets an assortment of warranty-upgrade packages. Support calls after the warranty expires will cost you, but three years is a long time for free phone calls in the meantime. IBM's Web site provides extensive documentation, downloads and access to technical information. The X31 doesn't include much printed documentation: just an eight-page setup guide, with a packing list, information on using the battery and a few other basics, along with an 80-page 'Service and Troubleshooting' guide. The X31 stores a disk image that you can use to restore software and system settings, taking up about 3GB of space. This is good since you don't have to carry a restore CD, but it's bad if the hard disk itself has problems. Our only sticking point is IBM's monitor policy: the company won't replace your LCD panel unless it has a whopping nine stuck or dead pixels.


Packaged Quantity 1
Platform Technology Intel Centrino
Built-in Devices ThinkLight
Embedded Security Trusted Platform Module (TPM) Security Chip
Notebook type Ultraportable (Under 4 lbs.)
Processor / Chipset
CPU Intel Pentium M 1.7 GHz
Cache L2 - 1 MB
Data Bus Speed 400 MHz
Chipset Type Intel 855PM
Features Enhanced SpeedStep technology
Cache Memory
Type L2 cache
Installed Size 1 MB
Type none
Type portable
Max Supported Size 2 GB
Technology DDR SDRAM
Speed 266 MHz / PC2700
Form Factor SO-DIMM 200-pin
Slots Qty 2
Empty Slots 1
Memory Speed 266 MHz
Memory Specification Compliance PC2700
Configuration Features 1 x 256 MB
Technology DDR SDRAM
Installed Size 256 MB
Rated Memory Speed 333 MHz
Resolution 1024 x 768 (XGA)
Widescreen Display No
Color Support 24-bit (16.7 million colors)
Diagonal Size (metric) 30.7 cm
Display Resolution Abbreviation XGA
Environmental Parameters
Humidity Range Operating 8 - 95%
Max Altitude Operating 9840 ft
Sound Emission 41 dB
Audio & Video
Graphics Processor AGP 4x - ATI Mobility Radeon
Sound Speaker, microphone
Hard Drive
Spindle Speed 4200 rpm
Type HDD
Installed Qty 1
Capacity 40 GB
Type TrackPoint, keyboard
Wireless Protocol 802.11a/b/g
Wired Protocol Gigabit Ethernet
CPU Type Pentium M
Manufacturer Intel
Clock Speed 1.7 GHz
Optical Storage
Drive Type no optical drive
Type none
Floppy Drive
Type none
Capacity 4400 mAh
Cells 6-cell
Technology lithium ion
Run Time (Up To) 5.5 hour(s)
AC Adapter
Input AC 120/230 V (50/60 Hz)
Output 56 Watt
Connections & Expansion
Slots 2 x memory (1 free)
1 x CardBus (1 free)
Interfaces 2 x USB 2.0 4 pin USB Type A
1 x display / video - VGA - 15 pin HD D-Sub (HD-15)
1 x infrared IrDA
1 x modem - phone line - RJ-11
1 x network - Ethernet 10Base-T/100Base-TX/1000Base-T - RJ-45
1 x parallel - IEEE 1284 (EPP/ECP) - 25 pin D-Sub (DB-25)
1 x IEEE 1394 (FireWire) 4 pin FireWire
1 x microphone - input - mini-phone 3.5 mm
1 x audio - line-in - mini-phone stereo 3.5 mm
1 x headphones - output - mini-phone stereo 3.5 mm
1 x docking / port replicator
Brand Lenovo
Product Line Lenovo ThinkPad X31
Model 2672
Localization English
Packaged Quantity 1
Compatibility PC
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.
Max Transfer Rate 56 Kbps
Data Link Protocol Ethernet, Fast Ethernet, Gigabit Ethernet, IEEE 802.11a, IEEE 802.11b, IEEE 802.11g
Remote Management Protocol CIM, DMI 2.0
Wireless LAN Supported Yes
Integrated Options ThinkLight
Security Trusted Platform Module (TPM) Security Chip
Features ThinkVantage Embedded Security Subsystem 2.0, administrator password, asset ID, hard drive password, power-on password, security lock slot (cable lock sold separately)
Compliant Standards ACPI 1.0b, ACPI 2.0, BSMI, CCIB, FCC Class B certified, GOST, MPR II, MPR III, NOM, Plug and Play, SASO, UL 1950, VCCI-II, cUL
Localization Language: English
Platform Technology Intel Centrino
Notebook Type notebook
Platform Windows
Hard Drive Capacity 40 GB
Embedded Security Trusted Platform Module (TPM) Security Chip
Diagonal Size 12.1 in
Color Support 24-bit (16.7 million colors)
Graphics Controller
Interface Type AGP 4x
Dimensions & Weight
Width 10.7 in
Depth 8.8 in
Height 1.2 in
Audio Output
Compliant Standards AC '97, DirectSound, SoundMAX
Manufacturer Warranty
Type 3 years warranty
Data Bus Speed 400 MHz
Chipset Type Intel 855PM
Environmental Standards
ENERGY STAR Certified Yes
Physical Characteristics
Weight 3.53 lbs
Type power adapter
Min Operating Temperature 41 °F
Max Operating Temperature 95 °F
Operating System / Software
OS Provided: Type Microsoft Windows XP Professional
Type Access IBM, Adobe Acrobat Reader, Norton AntiVirus 2003 (OEM), PC Doctor, ThinkVantage Access Connections, ThinkVantage Rapid Restore Ultra
Video Output
Graphics Processor ATI Mobility Radeon
Graphics Processor Series ATI Mobility Radeon
Video Memory
Technology DDR SDRAM
Installed Size 16 MB
Service & Support
Type 3 years warranty
Service & Support Details
Type limited warranty
Service Included parts and labor
Location carry-in
Full Contract Period 1 year, 3 years

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