The first CPU to reach a clock speed of 4 GHz was the Pentium 4 570 released in November 2004 as part of Intel's NetBurst microarchitecture, but this milestone wasn't achieved out of the box.
Intel unveiled the design of its Tejas processor in early 2003 with the ... By comparison, the 90nm Prescott-based Pentium 4 521 was set at the same frequency and had an 84w TDP while the upcoming ...