Adaptec AHA-2940U2 User Guide - Page 2

Bus Segments on the SCSI Card 2940U2W The SCSI Card 2940U2W features Adaptec SpeedFlex™ technology. SpeedFlex technology ensures that you get the most performance from your Ultra2 SCSI peripherals by electronically isolating the Ultra2 SCSI segment from the Ultra SCSI segment on the SCSI bus. With the SpeedFlex advantage, the SCSI Card 2940U2W can support Ultra2 SCSI peripherals at speeds up to 80 MBytes/sec while simultaneously supporting Wide Ultra/Ultra (legacy) peripherals at speeds up to 40 MBytes/sec. 68-pin Internal Ultra2 Connector 68-pin Internal Wide Ultra Connector 68-pin External Ultra2 Connector AIC-3860 Ultra2 SCSI AIC-7890 Segment Ultra SCSI Segment 50-pin Internal Ultra Connector NOTE Attaching Wide Ultra/Ultra SCSI peripherals to the Ultra2 SCSI segment of the SCSI bus causes the Ultra2 SCSI segment and any attached peripherals to drop to Ultra SCSI performance levels (40 MBytes/sec). Attaching only Ultra2 peripherals to the Ultra2 segment, ensures that all peripherals on the Ultra2 segment will perform at Ultra2 performance levels (80 MBytes/sec). Attaching an Ultra2 peripheral to the Ultra SCSI segment causes the Ultra2 peripheral to drop to Ultra SCSI performance levels instead of Ultra2 SCSI performance levels at which it is designed to run. 2