The Exadata Appliance configuration comes as a FULL Rack, Half Rack or Quarter Rack.
The Full Rack X2-2 has 6 CPUs per node with Intel Xeon 5670 processors and a total of 8 Database Server nodes, also known as compute nodes.
These SERVERS have 96GB of MEMORY on each node. A total of 14 Storage server cells communicate with the storage and PUSH the requested data from the storage to the compute nodes.
The Half Rack has exactly half the capacity. It has 6 CPUs per node with core Intel Xeon 5670 processors and a total of 4 Database Server nodes. It has 96GB of memory per database server node with a total of 7 Storage server cells