SIO

>

Short for super input/output or Super I/O, SIO is an integrated circuit on a computer motherboard that handles the slower and less prominent input/output devices shown below. When the Super input/output was first introduced in the late 1980's it was found on an expansion card, later this chip was embedded into the motherboard and communicated over the ISA bus. As ISA began to no longer be used with computers SIO communicated over the PCI bus. Today, super I/O communicates through the Southbridge and is still used with computers in order to support older legacy devices.

Some newer chipsets are combining the Southbridge and Super I/O chips into a single chip and referring to this chip as the Super Southbridge chip. Some manufacturers such as NVIDIA and SiS have even combined the Northbridge, Southbridge, and Super I/O into a single chip.

Identifying the Super I/O on your motherboard is often easy if you look for an integrated circuit that is labeled with a company's name that manufacturers Super I/O chips. Some common Super I/O manufacturers are Fintek, ITE, National Semiconductor, Nuvoton, SMSC, VIA, and Winbond.

Also see: Motherboard definition, Southbridge