With 256 MB of RAM originally and using Windows XP, the X31 was hurting for memory and thrashed a lot. Part of the reason for this is the huge amount of tray programs from IBM that are running. Running the Eclipse development studio, for instance, takes a much longer time. If the X31 is going to be used for anything more computationally intensive than Solitaire, an office suite, or a browser, invest in more memory.

The X31 flies once it gets going using X-bit Labs' Battery Eater 2.0 program, the battery lasts for about a 1 hour and 30 minutes or so in full use and without power saving turned on. With all the power saving options turned on, the battery can be extended for more than 5 hours without issues. The Intel PRO/2100 Wireless adapter also consumes power, so it's easy to get 5 hours of use out of the battery and browse the internet without being tied to a wire. The average power settings will allow 3 to 4 hours of use.

If are able to drain the battery entirety, it takes about 3.5 hours to charge the battery again if the X31 is off. If the X31 is in use, it can take about 4 hours to recharge the battery.

Without an optical drive being seen as a significant negative point or an advantage based on how you use the X31. A docking station allows for an extension in the X31's abilities and bringing along a better set of speakers, but is a bit costlier. Docking stations can run higher than $200. You can put another battery in the dock, expanding the life up to 8 hours, or a CD drive, which is expensive. In essence, if long battery life is important for you, get the Ultra Low-Voltage processor. If an optical drive is a essential and not required as a boot drive, get a USB optical drive, try CD-ROM emulation software like Alcohol 52%, or think hard about the ThinkPad T line or R series. At 3.6 pounds this laptop is very ultra weight.