ThinkPad T20 series

The IBM ThinkPad T20 series was a series of notebook computers introduced in May 2000 by IBM as the successor of the 770 series and the first model of the T-series, which exists today under Lenovo ownership. Four models were produced, the T20, T21, T22, and T23; the series was succeeded in May 2002 by the ThinkPad T30, but was produced until July 2003.

Features The T20 series succeeded the 600 series, adding new features such as S-Video output, an Ethernet port, and the UltraBay 2000 hot-swappable bay. The graphics card was upgraded from the 4 MB NeoMagic 256ZX that was used in the 600X, to an 8 MB S3 Savage (16 MB on T23 models) that was capable of rendering 3D graphics in hardware. The ThinkPad T23 was also the first ThinkPad laptop model to offer an optional Wi-Fi connection via a mini-PCI card, using wireless antennas that were built into the lid on select upper-end models. The T20 series originally shipped with either Windows 98, Windows 2000, or Linux, with later T23 models shipping with Windows XP. All T20 models were capable of running Windows 3.x, Windows 95, Windows NT 4.0, OS/2 Warp 4, or Windows Me as well as various Linux distributions. Additionally, the T23 was capable of running Windows Vista or Windows 7, if equipped with at least 512 MB of memory.

One common problem affecting the earlier T20 series (T20, T21, T22) was a hardware defect with the ADP3421 power regulator chip that caused the machine to experience instability, then eventually stop working and begin blinking the hard drive and power indicators. The machine would not power on. This became known as the “Blink of Death”.

In addition, on some T23 models, the rear memory slot could fail, rendering the machine only able to use up to 512 MB of memory, rather than 1 GB. Another common issue with the T23 was that one of the coils, near the CPU, could break off the motherboard due to cold solder joints. This caused multiple issues, including the inability to boot or hard lock-up/freeze.

Models ThinkPad T20 — First model shipped, featured a Pentium III at 650, 700 or 750 MHz, all with SpeedStep technology. This model shipped with either a 13.3" XGA TFT or 14.1" XGA TFT display, and shipped with an external floppy drive, a swappable CD-ROM or DVD-ROM drive, and a choice of a 6 GB, 12 GB, or a 20 GB hard drive. The T20 also had optional Ethernet (consumer installable via mini-PCI on all models), one USB 1.1 port, PC Card slot, and an S-Video output as standard features, and shipped with 128 MB of RAM (upgradeable to 512 MB using PC100 SO-DIMMs) ThinkPad T21 — Featuring an upgraded Pentium III processor at either 750 MHz, 800 MHz, or 850 MHz, the T21 featured either a 13.3" XGA TFT, 14.1" XGA TFT, or a new 14.1" SXGA+ TFT display (exclusive to 850 MHz models). This model shipped with a swappable CD-ROM or DVD-ROM drive, and a choice of a 10 GB, 20 GB or 32 GB hard drive. The T21 features either a mini-PCI modem card or an Ethernet/modem combo card, one USB 1.1 port, PC Card Slot, and 128 MB of RAM standard (upgradeable to 512 MB using PC100 SODIMMs). ThinkPad T22 — Featuring an upgraded Pentium III processor at either 800 MHz, 900 MHz, or 1.00 GHz, the T22 featured either a 13.3" XGA TFT, 14.1" XGA TFT, or 14.1" SXGA+ TFT display as standard. This model shipped a mini-PCI modem card or an Ethernet/modem combo card, one USB 1.1 port, PC Card Slot, a swappable CD-ROM or DVD-ROM drive, either a 10 GB, 20 GB or 32 GB hard drive, and 128 MB or 256 MB of RAM standard (upgradeable to 512 MB using PC100 SODIMMs). ThinkPad T23 — The final model of the T20 series, featuring the new Tualatin Pentium III-M at either 866 MHz, 1.00 GHz, 1.13 GHz, or 1.20 GHz (all with SpeedStep technology) and either a 13.3" XGA TFT, 14.1" XGA TFT, or 14.1" SXGA+ TFT display as standard. This model shipped with 2× USB 1.1 ports rather than only one, a 15 GB to 60 GB hard drive, a Mini-PCI Modem or Wireless card (on select models), a CD-ROM, DVD-ROM, CD-RW or combo (CD-RW/DVD) drive, and either 128 MB or 256 MB of RAM standard (upgradeable to 1 GB using PC133 SODIMMs). Does not suffer from the Blink of Death, unlike the other models.

Comparison +For all model versions/specifications: https://psref.lenovo.com/syspool/Sys/PDF/withdrawnbook/tawbook.pdfModelIntro-ductionDateWith-drawalDateBasePriceScreen OptionsTFTCPUOptionsMemory(std - max)VideoControllerAudioControllerHard DriveOptionsMiscInfoOperating SystemT20May 2000?? 13.3" XGA 1024×768 14.1" XGA 1024×768Intel Pentium III - 650, 700, or 750 MHz withSpeedStep Technology, 100 MHz Bus256 KB cache128 - 512 MB @ 100 MHzSDRAMViaS3 Savage IX88 MB SGRAMAGP 2xCirrusCS4264CS4297A6 GB12 GB18 GB20 GBUltrabay 2000ThinkLightUltraPort56K ModemLi-Ion Battery(4 hr)Windows 98SE

Windows 2000

Caldera OpenLinux eDesktop 2.4T21Oct 2000?? 13.3" XGA 1024×768 14.1" XGA 1024×768 14.1" SXGA+ 1400×1050Intel Pentium III - 750, 800, or 850 MHz with SpeedStep Technology, 100 MHz Bus256 KB cacheViaS3 Savage IX8 or IX8+8 MB SGRAMAGP 2x10 GB20 GB32 GBWindows 98SE Windows 2000

Caldera OpenLinux eDesktop 2.4T22Mar 2001??Intel Pentium III - 800 or 900 MHz, or 1 GHz with SpeedStep Technology100 MHz Bus256 KB cacheViaS3 Savage IX8+8 MB SGRAMAGP 2x15 GB30 GBWindows 98SE Windows 2000

Caldera OpenLinux eDesktop 2.4T22(SB)?? 14.1" XGA 1024×768 14.1" SXGA+ 1400×1050Intel Pentium III - 900 MHz or 1 GHz withSpeedStep Technology, 100 MHz Bus256 KB cache30 GB32 GB48 GBWindows 98SE Windows 2000T23Jul 2001?? 13.3" XGA 1024×768 14.1" XGA 1024×768 14.1" SXGA+ 1400×1050Intel Pentium III - 866 MHz or 1.13 GHz withSpeedStep Technology,133 MHz Bus512 KB cache128 MB - 1 GB @ 133 MHzSDRAMViaS3 Super Savage IXC1616 MB SGRAMAGP 4xCirrusCS429915 GB30 GB48 GBUltrabay 2000ThinkLightUltraPort56K Modem802.11b ModemLi-Ion BatteryWindows 98SE Windows 2000T23(Fall)Oct 2001?? 14.1" XGA 1024×768 14.1" SXGA+ 1400×1050Intel Pentium III - 1.0, 1.13 or 1.2 GHz withSpeedStep Technology,133 MHz Bus512 KB cache30 GB40 GBUltrabay PlusThinkLightUltraPort56K ModemWLANLi-Ion BatteryWindows 2000 Windows XP ProfessionalT23(Ed)Apr 2002??14.1" XGA 1024×768Intel Pentium III - 1.0 GHz withSpeedStep Technology133 MHz Bus512 KB cache256 MB - 1 GB @ 133 MHzSDRAM20 GB40 GB80 GBUltrabay PlusThinkLightUltraPortWLANLi-Ion BatteryWindows XP ProfessionalT23 (02)Jun 2002??Intel Pentium III - 1.0, 1.13 or 1.2 GHz with SpeedStep Technology133 MHz Bus512 KB cache30 GB40 GBUltrabay PlusThinkLight56K ModemWLANLi-Ion BatteryWindows 2000 Windows XP Professional

See also ThinkPad T Series

References