Later in 2005 the low-cost Celeron processor line based on the Pentium 4 will also move to 64-bit processing. Thus, by the end of 2005, the Pentium 4 family will offer 64-bit processing at almost every price point, making it clear that the long-awaited world of 64-bit processing has arrived.
For Further Research
Intel's official website for the Pentium 4 Extreme Edition http://developer.intel.com/products/processor/pentium4HTXE/index.htm
Intel's official website for the Pentium 4 http://developer.intel.com/products/processor/pentium4/index.htm
Intel's official website for Intel Extended Memory 64 Technology (EM64T) http://developer.intel.com/technology/64bitextensions/index.htm
Tom's Hardware digs into the new Extreme Edition and 600-series processors in its "Prescott Reworked: The P4 600 Series and Extreme Edition 3.73 GHz" report at http://www6.tomshardware.com/cpu/20050221/index.html
Anandtech analyzes the new members of the Pentium 4 family in "Intel Pentium 4 6xx and 3.73EE: Favoring Features Over Performance" at http://www.anandtech.com/cpuchipsets/showdoc.aspx?i=2353