SCSI Cables

The Three Types of SCSI - SE, LVD, HVD

SE SCSI Includes all SCSI devices that do not say "LVD" or "HVD" or "Differential". SE SCSI must be terminated with an SE terminator which includes passive (old), active (very common), FPT (a deluxe active), active negation (uncommon) or LVD/SE (best), and each is backwards compatible to work with the one listed before it. When in doubt, buy an LVD/SE terminator and save yourself headaches. The maximum speed on an SE SCSI chain is 40MB/second, and cable quality (such as "LVD" grade) will NOT change this.

LVD SCSI The latest and greatest in SCSI connectivity. HOWEVER, your entire SCSI chain (controller, terminators & devices) must be LVD or LVD/SE to achieve LVD benefits of speed, length and number of devices. If just one device is not LVD the entire chain will default to SE SCSI limitations (see above). The same goes for Ultra160 LVD or Ultra320 LVD - all devices on the chain must be Ultra160 LVD or Ultra320 LVD respectively.

HVD SCSI Also known as "Differential" SCSI, this is the least common SCSI type but allows longer cabling distances. HVD SCSI requires that the entire chain (controller, devices and terminators) be HVD (Differential). HVD cannot mix with SE or LVD SCSI. 


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