I bought a [single processor] Mac Pro on a whim (go figure). My intention was to see whether the Mac Pro 1,1/2,1 heatsink works in the Mac Pro 3,1 models. However, to my delight, the computer came with a magical second processor!
Feel free to scan the barcode.
Temporary setup. It probably should not live in front of my dresser.
That's a G5 carcass behind the Mac Pro.
Also, Apple certified FB-DIMMs are legit.
I <3 911s