Since IBM/Lenovo ThinkPad laptop does not ships with recovery CDs/DVDs. The factory restore image is store in the hidden partition. If you buy a 40GB IBM ThinkPad, end up you only get 33.xGB hard disk space. For a laptop, 4GB disk space is a precious waste. Furthermore, for geekery people like us(ahem), it’s hardly for us to perform factory restore state.
In order to throw away the hidden disk space, first you have to go into BIOS to remove hidden partition protection in Security > PreDekstop something and select Disable. A scary warning message will popup when you choose to disable it, don’t worry, it’s just a warning message, it won’t make you naked. Just select Okay!
WARNING! Before you decided to format the hidden partition, please create recovery CDs/DVDs for the sake of factory restore thingy in the future. Click here to learn how to create IBM/Lenovo ThinkPad Recovery CDs/DVDs.
Now, you can run FreeBSD/Ubuntu/Fedora/Mac OS X/Gentoo/DesktopBSD on the additional partition and dual boot with Windows XP.