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If you click on the Octo 2.26Ghz link and select picture #4 you'll notice that it shows TWO CPU/memory trays.

Pretty sure it's a mistake but 16 cores anyone?
 
Interesting:

Refurbished Mac Pro 2.8GHz Quad-Core Intel Xeon

Two 2.8GHz Quad-Core Intel Xeon processors
2GB (2 x 1GB) of 800MHz DDR2 ECC fully buffered DIMM
320GB Serial ATA 3Gb/s 7200-rpm hard drive
16x SuperDrive (DVD±R DL/DVD±RW/CD-RW)
ATI Radeon HD 2600 XT 256MB (two dual-link DVI ports)

$2,399.00
 
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