dell poweredge 2950 sata hard drive

Don't confuse SCSI with SAS (Serial-Attached SCSI) . 500gb external hard drive . 5 reel drive slot the 2950 doesn't take SCSI drives, but it will take SAS or SATA (backplane is SAS, which will take SAS or SATA) Individual drives may be up to 2TB, but your array can be larger As far as the controller goes, get the PERC 6