Informations about DC HC520 12To ?

[qwrty]

Hello

regarding HUH721212ALE601 and HUH721212ALE604 (DC HC520 12to) I nee some help to figure it out some point.
Maybe @MuscleLazy @napalm_atx could help

I bought some disks from two different ressellers, everythings works fine, but I have some question regarding those disks:

     Manuf.       Model               Serial                Interface       Capacity  Type  Firmware
----------------------------------------------------------------------------------------------------
  1) HGST         HUH721212ALE601     [REMOVE]              SATA            12000 GB  HDD   LEGNX3Q0
        HGST Firmware: LEOHX3Q0
  2) HGST         HUH721212ALE601     [REMOVE]              SATA            12000 GB  HDD   LEGNX3Q0
        HGST Firmware: LEOHX3Q0
  3) HGST         HUH721212ALE601     [REMOVE]              SATA            12000 GB  HDD   LEGNX3Q0
        HGST Firmware: LEOHX3Q0
  4) HGST         HUH721212ALE601     [REMOVE]              SATA            12000 GB  HDD   LEGNX3Q0
        HGST Firmware: LEOHX3Q0
  5) HGST         HUH721212ALE601     [REMOVE]              SATA            12000 GB  HDD   LEGNX3Q0
        HGST Firmware: LEOHX3Q0
  6) HGST         HUH721212ALE604     [REMOVE]              SATA            12000 GB  HDD   LEGNW9G0
        HGST Firmware: LEGNW9G0
  7) HGST         HUH721212ALE604     [REMOVE]              SATA            12000 GB  HDD   LEGNW9G0
        HGST Firmware: LEGNW9G0
  8) HGST         HUH721212ALE604     [REMOVE]              SATA            12000 GB  HDD   LEGNW9G0
        HGST Firmware: LEGNW9G0

I'm wondering:

1. Why firmware is different between "Firmware" column and the HGST Firmware statement for the HUH721212ALE601 model ? (GN mean Generic and OH mean OEM ?)
   Does this mean previous user flashed them with a generic firmware ?
   
   
2. HUH721212ALE604 firmware are up to date, but I see a firmware update for HUH721212ALE601 => LEGNX9U0 (HDDGURU Firmware)
   Can I update those disks with this firmware ?
   
   
3. HUH721212ALE601 are SED on the paper: data-sheet-ultrastar-dc-hc520
   But, hdparm seems report that the disk is not actually encrypting data (same result for all five disks):

hdparm -I /dev/sda

Security:
        Master password revision code = 65534
                supported
        not     enabled
        not     locked
        not     frozen
        not     expired: security count
                supported: enhanced erase

What do you think ?

Thank you very much

EDIT:
WD Support told me to flash VXGXB9U0.bin my 601s
What GX firmware standfor ?

 

[napalm_atx]

I dont know what GX standfor, bu i think this is something oem for other market. Yes you can update your HUH721212ALE601 with LEGNX9U0