In this link you didn't see 4 server is rack?
here is specification:
http://www.unisys.com/eprise/main/admin/corporate/doc/ES7000_Model_7600R_Spec_Sheet_Apr09.pdf
You can see there are 4 cell
CPU scalability • 4, 8, 12 or 16 processors (four processors per cell, one to four cells)
Maximum memory • Per cell: 256 GB (8 GB DIMMs)
• Per system: 1 TB (8 GB DIMMs)
This isn't nod?