Choose Your Product
No Product SelectedSelect Product
Detailed specifications - ThinkPad X31
CommunicationsOperating environmentStorage

  • Chipset is AD1981B
  • One 0.5W internal speaker (mono)
  • 16-bit and 8-bit stereo playback and recording
  • Sound Blaster compatible
  • DirectSound 3D positional audio
  • Volume up, down, and mute buttons
  • Three 1/8" audio jacks:
    • One for external stereo speakers or headphone
    • One for an external microphone
    • One for line-in
  • 85 SBCS key keyboard with embedded numeric keypad and integrated TrackPoint(TM) with enhanced features
  • 90 DBCS key keyboard with embedded numeric keypad and integrated TrackPoint(TM) with enhanced features for Japanese systems
  • Embedded numeric keypad
  • The keyboard has a Fn key which is a special key and is located in the lower left corner. The Fn key allows the user to instantly activate the following operational features by pressing the Fn key and a designated function key: - Standby/Suspend/Hibernation - Switching between Display devices - Power management mode
  • ThinkPad button, allowing one-touch entry into Access ThinkPad
  • ThinkLight which illuminates the keyboard in low light conditions
  • Uses DDR PC2100 or 2700 2.5V SO-DIMM memory, no support for parity/ECC
  • Total of 2 memory slot, 1 slot prepopulated with either 256MB or 512MB depending on model
  • Supports up to two 1GB SO-DIMMs
  • Supports maximum memory up to 2GB
  • TrackPoint(R) with Press-to-Select, Internet scroll, and magnifying glass features for accurate and convenient control
  • Dual-mode, high-performance Mobile Intel(R) Pentium(R) Processor at 1.3GHz, 1.4GHz, 1.5Ghz, 1.6GHz, 1.7GHz.
  • Enhanced Intel SpeedStep(TM) technology
  • 1024 KB onboard L2 cache memory

Infrared (IR)
  • IR transceiver for wireless file and data transfer and printing.
  • Speeds up to 4 Mbps.
  • Compatible with the Infrared Data Association (IrDA) IR data link specification
  • Sensing Distance: 1 m
  • Sensing Angle: + 15 degree, -15 degree horizontally
  • 56K v.92
  • Available as either a single CDC card or in combination with the Bluetooth CDC card
Note: Public network download speeds are limited to 53kbps. Upload speeds are limited to 31.2kbps. Actual speeds depend on many factors and are often less than the maximum stated.
  • Ethernet
    • 10/100 Ethernet or 1GB Ethernet soldered on system board
    • 802.11b wireless, (depending on model)
    • Option part numbers for network cards
  • Wireless
    • Available as either Dual-band 802.11a/b, Intel 802.11b, or Cisco 802.11b Mini PCI cards
    • Click here for FCC information
  • Bluetooth
    • Available on selective models as a Communications Daughter Card

  • One Mini PCI type III slot
  • One Communications Daughter Card slot
  • Ultrabay is available via the ThinkPad X3 UltraBase
External ports
  • Two USB (One on right side, one in back) version 2.0
  • One Ethernet RJ-45 with 2 LEDs
  • One RJ-11 for modem enabled systems
  • Type II (5mm thick) Compact Flash slot
  • One IEEE 1394
  • One DB-15 external display
  • Additional connector supports the optional Port Replicator and dock
  • Audio line in, audio line out, and microphone in ports
  • Parallel port
PC Card
  • Conforms to the PC Card Standard 95
  • The Type II slot can accommodate one Type I or one Type II
  • Both 16-bit and 32-bit cards are supported.
  • PCMCIA 2.1 standard

Operating environment
Physical specifications


  • Width: 273 mm (10.7 in)
  • Depth: 223 mm (8.8 in)
  • Height: 24.9 mm (0.98 in) - 30.2 mm
  • Weight:
    • Minimum: 1.63 kg (3.6 lb)
    • Maximum: 1.66 kg (3.7 lb)
Note: All dimensions are approximate.
Agency approvals
  • FCC Class-B certified to comply with FCC Rules, Part 15
  • VCCI Class 2
  • CB Report
  • UL-1950
  • C-UL 1
  • NOM (Mexico)
  • SASO
  • CCIB/CCEE (for China)
  • BSMI (for Taiwan)
  • MIC (for Korea) 1
  • SMA 3548(Australia and New Zealand)
  • Gost (Russia) 1
  • MPR-II/MPR-III(B) (Sweden)
  • CE Mark

AC Adapter
  • AC adapter: This ac-to-dc converter supplies the necessary power to the computer. The ac adapter also charges the battery pack when it is installed in the computer.
  • Universal AC adapter (56 W):
    • Input is 100/240 V ac, 1.2/0.7 A, 50/60 Hz
    • Output is 16 V dc, 3.5 A
  • The battery pack is an internal power source to the computer when the ac adapter is not available. The battery pack is rechargeable and is charged using the ac adapter with the system.
  • A six-cell Li-Ion battery pack is shipped with the system.
  • Li-Ion battery pack: 10.8 V, 4.4 AH
  • Approximate operation and charging hours are:
    • Power off/suspend charging: 3.3hr **
    • Charging during operation **
      • 3.0 hours minimum
      • 4.0 hours typically
      • 7.0 hours maximum
    • Battery operation: 4.5 - 5 hr *

Results obtained using eTesting Labs Inc's BatteryMark(TM) Version 4.0.1. Battery life will vary based on many factors including screen brightness, applications, features, power management, battery conditioning, and other customer preferences.
* BatteryMark(TM) is a trademark of Ziff Davis Publishing Holdings Inc., an affiliate of eTesting Labs Inc., in the U.S. and other countries.
** Recharge time will also vary

  • Security Chip (TCPA/Crypto 3) on selected models
  • Locking device in the security slot provides physical security.
  • A Power-on password (POP) protects the system from unauthorized
    use. If a POP is set, the password prompt appears:
    • Each time the system is turned on
    • When the system is returned to normal operation from suspend mode
  • A Supervisor Password provides a higher level of security than the POP. The Supervisor Password protects the system functions from being used by unauthorized users, and protects the hardware configuration from unauthorized modification.
  • A hard drive Password(HDP) protects hard drive data from unauthorized users. Once HDP is set, data on the hard drive cannot be accessed without the correct HDP. Because the HDP is stored in the hard drive, the data remains protected even if the hard drive is removed to another system. The HDP password prompt appears:
    • Each time the system is turned on

Operating system
The following operating systems are supported on the ThinkPad X31 systems:
  • Microsoft Windows 98 Gold
  • Microsoft Windows 98 Second Edition
  • Microsoft Windows NT Workstation 4.0 with Service Pack 6a
  • Microsoft Windows 2000
  • Microsoft Windows XP Professional
  • Microsoft Windows XP Home
Note: Preloaded software utilizes the disk-to-disk recovery method. Previous versions of these operating systems are not supported.

Optical drive
  • Available via USB or X3 UltraBase Media Slice's Ultrabay 2000 slot
Floppy drive
  • Available via USB or X3 UltraBase Media Slice's Ultrabay 2000 slot
Hard drive features
  • Standard with either 20GB or 40GB
  • Supports one additional hard drives which can be used concurrently to offer expanded storage
  • S.M.A.R.T technology to issue an alert if a hardware failure is pending
  • ATA Bus Interface
  • 4200 or 5400 rpm
  • Although you can upgrade the hard drive, it is not designed to be removed and reinserted on a regular basis. Repeated and frequent removal, for purposes other than to upgrade for greater capacity, can cause damage to the system. The Ultrabay 2000 hard drive adapter is designed to provide this flexibility with a second hard drive in the Ultrabay 2000


Large, brilliant 12.1inch XGA (1024 x 768) active matrix TFT display

  • All displays are measured diagonally.

Graphic Controller
Video chipsets:
  • ATI Mobility RADEON M6C-16h
  • 16MB of memory integrated on chip
16MB ATI Mobility RADEON
ResolutionLCD Color depth
640x480256, 64k, 16M
800x600256, 64k, 16M
1024x768256, 64k, 16M
1280x1024256*1, 64k*1, 16M*1
1600x1200256*1, 64k*1
2048x1536256*1, 64k*1

ResolutionSupported refresh rates in Hz for external monitors
640x48060, 72, 75, 85, 90, 100, 120, 160 Hz
800x60060, 70, 72, 75, 85, 90, 100, 120, 160 Hz
1024x76860, 70, 72, 75, 85, 90, 100, 120, 150*3, 160 Hz*3
1280x102460, 70, 75, 85, 90*3, 100*3, 120 Hz*3
1600x120060*3, 75*3, 85*3, 100*3, 120Hz*4*3
2048x153660*3, 66*3, 70*3, 75Hz*4*3
*1 Supported only in panning mode on LCD
*2 Supported at external monitor only. When the LCD and external monitor are used at the same time, the refresh rate may be lower.
*3 Refresh rate not supported in 16M color depth.
*4 Refresh rate not supported in 64K color depth.

If you are unable to find what you are looking for, please do try the following options:
1. Lenovo Assisted Search
2. Product usage and general troubleshooting tips
3. Lenovo Support Forum
4. Technical Support Call Centre

Country Availability
Document ID : PD014256
Legacy Document ID : MIGR-58212
Last Updated :
Copyright © Lenovo 2013, all rights reserved
Was this page helpful to you?YesNo

Select Task
Drivers & Software  
Guides & Manuals  
Diagnose & Fix  
Warranty & Services  

Support Help Index
Warranty Lookup
Product Detail
Technical Specifications - PSREF
Driver Matrix
KnowledgeBase Featured Articles
Community KnowledgeBase
Community Forums
Lenovo EMC
Windows 8 Support