Hello,
We would like to inform you that the Intel® Xeon Phi™ Coprocessor 5120D is designed for OEM (Original Equipment Manufacturers) exclusively. The co-processors fully compatible with the S2600GZ board on a "2U" system are the following:
Intel Xeon Phi Coprocessor 7120P
Intel Xeon Phi Coprocessor 3120A
Intel Xeon Phi Coprocessor 5110P