Note that in terms of performance they would be ranked 3100 4000/200 slowest 4000/300 4000/90 So if you can find a 4000/90 that would be the way to go. Also the 200 and 300 are Qbus based and thus not easy to attach SCSI disks to. All in all you want a 4000/90. (or 4000/105, or 4000/95). --Chuck