Compellent SCv3020 disks not accepted

Hi, 

I was running out of space in my system and decided to buy new disks to increase the current pool with 15 KRPM disks. Since Dell is not selling disks anymore for the SC product line, I decided to give it a try with a third-party vendor. 

I have installed 3 SAS disks 900 GB 15 KRPM, 2.5", P/N 436D2 and the Manager Console is marking them as failed. The specific error is: "The system can't accept disk 42 in position 1-19 with serial number XXXXX and part number Dell CN0436D2SGW0078G00Q0A00 because the hard disk line is not compatible with the system. "

The Dell P/N seems to be completely compatible with SC systems, but I'm not sure what is failing. The system is currently out of warranty and has FW version 7.4.21.4

I will appreciate any comment or advice. 

Regards, 

J. Luna