Just spotted this bit of Info over at TheInquirer.net.

A firm on the show floor here in Taipei is offering the chance to buy an Xbox that uses a Celeron 1.4GHz/256K cache chip rather than the feeble 733MHz Pentium III that ships with the console. The chip inside this machine can be switched from a so called ?standard speed? of 740MHz to a ?turbo? speed of 1480MHz.

Update: Sorry about that! the Link is now fixed.