Integrated Circuit Technology
1971: The Intel 4004 was a 4-bit central processing unit (CPU) released by Intel Corporation in 1971. It was the second complete CPU on one chip (only preceded by the TMS 1000), and also the first commercially available microprocessor. Such a feat of integration was made possible by the use of then-new silicon gate technology allowing a higher number of transistors and a faster speed than was possible before.
1974: The Intel 8080 was the second 8-bit microprocessor designed and manufactured by Intel and was released in April 1974. It was an extended and enhanced variant of the earlier 8008 design, although without binary compatibility. The initial specified clock frequency ...view middle of the document...
The 8086 gave rise to the x86 architecture which eventually turned out as Intel's most successful line of processors.
1993: Pentium microprocessor was introduced on March 22, 1993. Its microarchitecture, dubbed P5, was Intel's fifth-generation and first superscalar x86 microarchitecture. As a direct extension of the 80486 architecture, it included dual integer pipelines, a faster floating-point unit, wider data bus, separate code and data caches and features for further reduced address calculation latency. In 1996, the Pentium with MMX Technology (often simply referred to as Pentium MMX) was introduced with the same basic microarchitecture complemented with an MMX instruction set, larger caches, and some other enhancements.
2001: Itanium is a family of 64-bit Intel microprocessors that implement the Intel Itanium architecture (formerly called IA-64). Intel markets the processors for enterprise servers and high-performance computing systems. The architecture originated at Hewlett-Packard (HP), and was later jointly developed by HP and Intel.
2010: Gulftown or Westmere-EP is the codename of a six-core hyperthreaded Intel processor able to run up to 12 threads in parallel. It is based on Westmere microarchitecture, the 32 nm shrink of Nehalem. Originally rumored to be called the Intel Core i9, it is sold as an Intel Core i7 The first release was the Core i7 980X in the first quarter of 2010 along with its server counterpart, the Xeon 3600 and the dual-socket Xeon 5600 (Westmere-EP) series using identical chips
Source for this information (Wikipedia, Microprocessor Transitor Count History)