VLB - Vesa Local Bus

Developed in 1992 by the Association VESA bus VLB is dedicated to graphics cards but was also used by the card input - output (E-IDE connection, reader Disk, Serial ports and parallel). It is specific for 486.

The number of connectors VLB is a maximum of 3 board, including two really usable. This is an extension of 16 bits data from a ISA bus 16 bit. The data bus is 32 bits as the 486. Added directly to the connector takes the output signals of a 486. This bus is dedicated to him. The speed of the extension is the departure of 33 Mhz (The ISA is in 8 Mhz). Some versions have evolved up to 40 and even 50 MHz, depending on the evolution of the external bus (FSB) of 486

The bus VLB comes in two versions: A and B. The B is connected to processor via an interface circuit a more sophisticated simple buffer. The performances are identical.

He was replaced by PCI bus for the Pentium, which uses a data bus of 64 bits, even if the PCI bus is 32 bit, but Plug and Play.