Pentium® 4 (Socket 423)

Introduced on November 20th, 2000 at speeds of 1.4 and 1.5GHz the Pentium 4 was the first product to use Intel's new Netburst architecture.
Netburst was designed to run at much higher clockspeeds than previous architectures with Intel stating on launch that it would scale past 10GHz in future generations of processor. This was achieved by increasing the pipeline length to double that of the P6's, 20 stages for the Willamette instead of 10 for the Pentium II and III.
The increased pipeline length brought with it some performance penalties however, any pipeline stalls would have double the effect meaning that at launch most benchmarks saw little if any performance benefit compared to a high-end Pentium III, and in some cases performance could even be lower.
As the Willamette core scaled to 2GHz performance advantages over the Pentium III became evident, however power consumption was also climbing with a TDP of 71.8W at 2GHz, compared to 29W for a 1GHz Coppermine.

The only chips released on Socket 423 were those based around the Willamette core and all had the same main feature set including a quad-pumped front-side bus giving an effective 400MHz frequency and new SSE2 instructions.

Archived Pentium® 4 800MHz

Identical pair of early Pentium 4 engineering samples, pulled from a lab bin.
Untested.

Archived Pentium® 4 1.4GHz

Brand new, still sealed in box. Received as a gift.

Archived Pentium® 4 2GHz

Production, retail stepping. Pulled from a lab bin.
Untested.