Part Number(s) : 2Z691-5269-A
MacOS X 10.3.7 PowerMac G5 DVD (2 disk)
Original Apple OSX 10.3.7 (Panther) system install disks for PowerMac G5 including hardware test. The OSX DVD which will install a complete fresh system. Although this disk is branded for the PowerMac G5, it will instal OSX on any DVD equipped system capable of running OSX 10.3.
http://www.thebookyard.com/product.php?products_id=5678
PowerMac G5 OS X 10.3.4 (Panther) Software Install DVD
Item #:
2Z691-5094-A 1000949
Compatible with eMac (ATI Graphics), eMac (1.0 GHz G4), eMac (USB 2.0), iBook ClamShell, iBook (Dual USB), iBook (Late 2001), iBook (14.1 LCD), iBook (16 VRAM), iBook (14.1 LCD 16 VRAM), iBook (Opaque 16 VRAM), iBook (32 VRAM), iBook (14.1 LCD 32 VRAM), iBook (800/900 MHz 32 VRAM), iBook (14.1 LCD 900MHz 32 VRAM), Except - iBook G4 (Mid 2005), all iMac Flavor, all iMac Flat Panel, iMac G5 (17-inch), iMac G5 (20-inch), Mac Mini (original), Power Macintosh G3, Macintosh Server G3, Power Mac G4 & Macintosh Server G4 - all models, Power Mac G5--all models Except - (Power Mac G5 (Early 2005), Power Mac G5 (Late 2005), PowerBook G3 (Bronze Keyboard), PowerBook G4 - all models Except - PowerBook G4 (Double-Layer SD), Xserve G5, Xserve G5 (Cluster Node), Xserve G5 (January 2005), Xserve G5 (January 2005 Cluster Node)
http://www.welovemacs.com/2z6915094a.html
But yours, the Late 2005 2.0 came with... 10.4.2 (8E90), no idea on the 2z691 number though.