Hello,   No that is not possible or supported.  There are some specific hybrid models, that have some SSDs and the balance 10 or 15K SAS drives.   Also you have to use DELL/EQL firmwared drives in a PS6110.  You can't use standard off the shelf drives.   Regards,   Don 
Can I initialize this system safely with only 12 slots populated with SSDs? Followup question:Is it possible to mix drive types in these newer equallogic chassis?  I know it's not possible on older systems, but i've heard rumors that suggest i can use 12 SSDs and 12 SAS/NL-SAS disks in the same chassis.  I want to hear it from Dell though before trying.
PS6110S with 12 SSDs