IBM ThinkPad 600

The IBM ThinkPad 600 series was a series of notebook computers introduced in 1998 by IBM as the immediate predecessor to the T-series which still exists today under Lenovo ownership. Three models were produced, the 600, 600E, and 600X; the series was succeeded in 2000 by the ThinkPad T20 series.
Features.
The 600 series was designed to be a more portable version of the 770 series, featuring slimmer dimensions and a weight of around 5 pounds (2.3 kg), by using lightweight but strong carbon fiber composite plastics. The 600 series also introduced the new UltraSlimBay (not to be confused with the UltraBay Slim as found on the later T40/T60 series), as well as easily interchangeable RAM and hard drives; all 600 series machines shipped with 32 or 64MB of RAM integrated on the motherboard from the factory.
The 600 series originally shipped with either Windows 95 or Windows NT 4.0, with later models shipping with Windows 98 or Windows 2000; all 600 models could also run Windows 3.x, OS/2 Warp 4, Windows Me, or Windows XP as well as various Linux distributions. None of the 600 series models included wireless adapters or Ethernet ports as an option, but these could be added through a third-party PCMCIA/CardBus card.
One common problem of the 600 series was a battery defect, where the battery would discharge rapidly or otherwise have a poor battery life; use of a third-party battery as well as a BIOS update can help alleviate this problem.