I recent installed a replacement server for a customer and since they had installed a Compaq SDLT 320 drive in their old server I transfered the tape drive to the new server.  

The new server is a Dell PE 2900 with a SCSI card just for the tape drive, winning Win2k3 SBS R2.  We're using Backup Exec 11d SBS edition.  We are only backing up the server with with the tape drive, there are no other servers in the environment.

The first few backup jobs we ran, ran at a reported Job Rate of ~1024 MB/min.  Since then the jobs have been running at a mere 272 MB/min, which is actually a little slower than on the old server.

I just reviewed the job configuration and noticed that the compression was set to "hardware otherwise software".  I normally never set that, opting for "hardware, otherwise none", I'm chalking that up, currently to a mis-click.  

Has anyone experienced anything like this or have any suggestions as to why this might happen?

I'm going to set up a performance log to see if the disk gets jammed up, or if CPU goes wild during the back job.

Thanks!