Intel 8008
From Computer History Wiki
The Intel 8008 CPU, the world's first 8-bit microprocessor. Introduced in 1972. 0.5MHz clock frequency, or for the 8008-1 variant pictured to the right, 0.8MHz. The 0.8MHz variant was available as early as June 1972[1]
References
[1]http://www.youtube.com/watch?v=GG6goCIWCYY (Craig Solomonson's 1972 Intel Microcomputer)