Depending on their architecture, the computers are likely to feature one of the following hard drive buses.
An SCSI connector is located at the rear of the Computer; the SCA chanel is found on the internal bus of the SPARC Worstation. It can be basicaly seen as an SCSI bus that provides power supply and assigns SCSI ID to the peripherals.
This is found for example in an Ultra 5 or Ultra 10 computers This bus is the one you can find in your intel box.
This is the FiberChannel bus. It is used by the SunBlade 1000 workstation.