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according to the serial he put up he has,

Nice Name: PowerMac G5 PCI-express (Late 2005)
Machine Model: PowerMac11,2
Name: PowerMac G5 (Late 2005)
ModelCode: g5_late_05
Family name: A1177
Model Number: M9590
Group1: PowerMac
Group2: G5
Generation: 5
CPU speed: 2.0GHz
Colour: Aluminium
Production year: 2006
Production week: 25 (June)
Production number: 36 (within this week)
Model introduced: 2005
Memory - flavour: DDR2-L-533
Memory - number of slots: 8
Memory - maximum total: 16GB
Memory - largest module: 2GB
Factory: CK (Cork, Ireland)
 
When you install it, just be sure you install it correctly. G5 ram will not work at all if it's not paired correctly.
 
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