VESA Local Bus

The VESA Local Bus (usually abbreviated to VL-Bus or VLB) is a short-lived expansion bus introduced during the i486 generation of x86 IBM-compatible personal computers. Created by VESA (Video Electronics Standards Association), the VESA Local Bus worked alongside the then-dominant ISA bus to provide a standardized high-speed conduit intended primarily to accelerate video (graphics) operations. VLB provides a standardized fast path that add-in (video) card makers could tap for greatly accelerated memory-mapped I/O and DMA, while still using the familiar ISA bus to handle basic device duties such as interrupts and port-mapped I/O. Some high-end 386DX motherboards also had a VL-Bus slot.