ThinkPad T400 (14.1-in WXGA TFT (1280 x 800) LED Backlight, Mobile Intel GM45 Express chip set, Mobile Intel GMA 4500MHD, Integrated fingerprint reader, Intel Core 2 Duo processor P8600, 250 GB / 5400 rpm HDD, DVD Recordable drive, ExpressCard slot, PC Card slot, 2 GB memory, Intel Wireless WiFi Link 5100 AGN (1 x 2), Genuine Windows 7 Professional 32, 6-cell Li-Ion battery) Windows XP Professional preinstalled through downgrade rights from Genuine Windows 7 Professional