P6 was the microarchitecture for Intel's for desktops and servers as a successor to P5. Introduced in 1995 and continued until 2000, P6 was fabricated using 350 nm and 250 nm processes. P6 was obsoleted by NetBurst in late 2000.
P6 was manufactured on the 0.35 µm process initially and later enjoyed a process shrink down to 0.25 µm, allowing for considerably lower voltage and higher clock speed at a smaller silicon die area. The shrink introduced a 5th metal layer which further reduced RC delay and die area. Intel claimed the channel area was reduced by 50% with the introduction of the 5th layer. The 5th layer also enabled Intel to support C4 packaging.