adding 300GB scsi drives to a PE2600 question

[Adam Williams]

I purchased 6 300GB u320 from a dell authorized reseller for a PE2600.  
They just came in.  Do the drives need to have their jumpers set to a 
scsi id, or does just inserting a drive into bay 0 give it scsi id 0 to 
the controller, another drive put into bay 1 gets scsi id 1 on the 
controller, etc?  the drives have instructions on how to set the SCSI id 
on the labels, but they didn't come with any jumpers.