We're using an Adaptec aic7xxx Ultra160 SCSI card with an external SCSI box
including two 160 MB/s drives and two 80MB/s drives.
2.2.14-12 kernel recognizes the card as 160M, but all of those drives
are detected as 80MB/s, even though the first two of them are actually
I installed kernel 2.2.12-20 on the side, and booted using it. The two
drives were correctly detected as 160MB/s. Seems to work with the older
For a very long time the driver kept some 160 drives at 80 to deal with
fundamental problems. The new drivers finally fixed this in 2.4.
Alan (tidying bugzilla)