TODAY AMD UNLEASHES its new Athlon XP processor on an unsuspecting world. AMD's Athlon processor gets a new name, a revamped design, a new look, and a controversial new marketing scheme. The Athlon XP is AMD's attempt to win back the PC processor performance crown from Intel, whose 2GHz Pentium 4 just edged out the 1.4GHz Athlon in our last round of tests. This new Athlon XP chip runs at only 1.53GHz, but it's likely to take Intel's 2GHz wonder to the woodshed. Read on to find out why.