I install Dual core xeon SL8MA in my PE2850 and get such error message

"Unsupported CPU stepping: 48"

 

What am doing wrong?

 

Version of my bios is A07 

 

Support of SL8MA Declared in bios relesase notes:

Changes from A05:

* Updated Intel(R) Xeon(TM) Dual-Core Processor with 2x2MB L2 Cache A0 Stepping
  Microcode (Patch ID=0C).