IBM 5590 2780 Ctlr w/Aux Write Cache

• SCSI RAID cotroller
• 757MB Cache

IBM 5590 includes a #2780 PCI-X RAID Disk Controller with 757MB of write cache and a secondary IOA with 1.5GB of auxiliary maximum compressed write cache. The #2780 and the secondary IOA each require one PCI-X slot and must be installed together in the same system unit or I/O unit/drawer/tower. #2780 and the auxiliary write cache IOA are connected by the provided SCSI cable. Feature #2780 will not appear on IBM ordering, shipping, or inventory documentation. The connecting SCSI cable is attached to port four of the #2780, reducing the number of SCSI buses that support disk drives from four to three. The reduction of SCSI buses may also reduce the number of disk drives supported by the #2780, depending on the system unit or I/O unit/drawer/tower in which the #2780 is installed. No disk drives are driven by the auxiliary write cache IOA.