The Cyrix Cx486 had a DX model called the Cx486DX-33QP which had a bus speed of 33 MHz, a measurement of the clock speed electronics are driven by.
Models of Cx486DX 33 MHz Hertz are commonly expressed in multiples: kilohertz (10 Hz, kHz), megahertz (10 Hz, MHz), gigahertz (10 Hz, GHz), terahertz (10 Hz, THz), petahertz (10 Hz, PHz), exahertz (10 Hz, EHz), and zettahertz (10 Hz, ZHz). It is also used to describe the clock speeds at which computers and other electronics are driven. 
