Appendix B. Ubuntu Desktop 64-Bit Discs
As I mentioned in Chapter 1, the version of the Ubuntu Desktop CD that comes with this book is designed to work with i386 processors, in either PCs or Intel-based Macs. It will also work with AMD64 or Intel Core 2 processors, albeit not in 64-bit mode. In order to use Ubuntu with these processors (or any other machine based on AMD64 or EM64T architecture) in 64-bit mode, you must get a different disc on your own. There are a few ways to do this: downloading an ISO (disc image) and then burning it to disc yourself or ordering the disc from an online Linux disc provider.