A term used to describe a 8-bit wide bus operating Ultra (between 20 MHz and 40 MHz). The maximum data rate of a Ultra SCSI device or bus is 40 Mbytes/sec.
A standard for SCSI data transfers. It allows a transfer rate of up to 40 MBytes/sec over an 8-bit SCSI bus, and up to 80 MBytes/sec over a 16-bit SCSI bus. The STA (SCSI Trade Association) supports using the term "Ultra2 SCSI" over the older term "Fast-40."
This flavor of the SCSI interface supports data transfer rates up to 80 MB/second. Medéa VideoRaids also incorporate a Low Voltage Differential (LVD) interface - with a compatable host adapter this allows longer cabling.