Lenovo Thinkpad T400 tested and working hardware Processor: Intel Core 2 Duo P8600 (“Intel Penryn” 6 MiB L3 cache) at 2.40 GHz
Audio: CX20585 HDA Intel (UniAud driver) tested svn 4349
Video : ATI Mobility Radeon 3470 w/ 256MB (hybrid switching) (SNAP 3.1 driver)
screen: 1400 x 900 WXGA+ LED backlit (FRU 42T0729)
USB: Intel 82801G (ICH7) USB UHCI/EHCD controller (IBM OS/2 USB 1.1/2.0 stack (basic/msd/mouse/keyb) 12/21/05 - v10.162)
Network: 82567LF Network Adapter (E1000E.MAC driver)
Wireless Network: Intel PRO/wireless 3945ABG Network Connection (GenMAC ver 2.1 driver)
Wireless Bluetooth: 2.0 (not tested)
Infrared Adapter: none
Storage Controller: IDE_0 xATA Controller ICH7 (DANIS506/OS2DASD driver)
chipset: Nehalem i686
memory: 4G (3023G usable)
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What did not work (to do list):1024x900 maximum resolution with Panorama driver (device capable of 1440x900).
Fingerprint reader not functional.
USB flash storage not ejecting properly. Gives message: "Forced Removal -- Possible data loss"
Wireless Bluetooth 2.0
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Performance:
Boot time: 33 seconds
mem: 3034 GB
CPU load on idle: 1%
User load on idle: 0.5%
Load on installing Openoffice 3.2 (WarpIN): 63%
CPU: Intel Core 2 Duo with Penryn-3M on Nehalem board
My review:
At Home: perfect

At work: needs a workaround to use with newest server equipment.
This laptop weighs 5 pounds but will rest nicely on a rack wall mount or cabinet. For the Tower configuration, I would place it on a sturdy table above the server unit (placing the tower in a well ventilated space).
The mid-2008 Thinkpad T400 is an ideal computer for Warp Server for eBusiness and eComstation. It is a good choice for those who need a tool to monitor servers that use Penryn-WM and Wolfdale-DP class 45nm microprocessors. The relatively long wavelength places some limitations on its usage with today’s high-end devices with 14nm technology but there are workarounds. As a basic maintenance and monitoring tool, the T400 is easy and effective. In addition, the low price makes it a very good device for home or small office use. There are many available to buy used and refurbished. As an everyday laptop, I feel it is a bit too heavy at 5 pounds. The battery protrudes from the rear of the chassis The use of plastic parts makes it feel flimsy, but it is in fact, very durable. I am using CAT 5 cables with a 100Mbips powered ethernet