Update RN516 BIOS to support VT-x for Virtualbox

I have VirtualBox + phpVirtualBox up and running on my RN516 (running OS 6.4.1) but am unable to launch any 64 bit VMs due to VT-x not being enabled in the BIOS (VERR_VMX_MSR_ALL_VMX_DISABLED error). Is there a place where I can find newer versions of the BIOS, or possibly a way to simply enable VT-x? I am comfortable doing any necessary shell commands or config changes to make this happen. Thanks!

Here are the contents of my bios_ver.log:

::::::::::::::
/sys/class/dmi/id/product_sku
::::::::::::::
RN516
::::::::::::::
/sys/class/dmi/id/product_name
::::::::::::::
ReadyNAS 516
::::::::::::::
/sys/class/dmi/id/product_uuid
::::::::::::::
0097272A-D21D-B211-8000-4494FC6E0C04
::::::::::::::
/sys/class/dmi/id/board_name
::::::::::::::
ReadyNAS 516
::::::::::::::
/sys/class/dmi/id/board_asset_tag
::::::::::::::
To be filled by O.E.M.
::::::::::::::
/sys/class/dmi/id/chassis_serial
::::::::::::::
To Be Filled By O.E.M.
::::::::::::::
/sys/class/dmi/id/product_version
::::::::::::::
06/06/2013 ReadyNAS-516 V1.0
::::::::::::::
/sys/class/dmi/id/chassis_vendor
::::::::::::::
NETGEAR
::::::::::::::
/sys/class/dmi/id/modalias
::::::::::::::
dmi:bvnAmericanMegatrendsInc.:bvr4.6.5:bd06/06/2013:svnNETGEAR:pnReadyNAS516:pvr06/06/2013ReadyNAS-516V1.0:rvnNETGEAR:rnReadyNAS516:rvrTobefilledbyO.E.M.:cvnNETGEAR:ct3:cvrToBeFilledByO.E.M.:
::::::::::::::
/sys/class/dmi/id/chassis_version
::::::::::::::
To Be Filled By O.E.M.
::::::::::::::
/sys/class/dmi/id/bios_date
::::::::::::::
06/06/2013
::::::::::::::
/sys/class/dmi/id/bios_version
::::::::::::::
4.6.5
::::::::::::::
/sys/class/dmi/id/product_serial
::::::::::::::
3C82360L00ED4
::::::::::::::
/sys/class/dmi/id/sys_vendor
::::::::::::::
NETGEAR
::::::::::::::
/sys/class/dmi/id/bios_vendor
::::::::::::::
American Megatrends Inc.
::::::::::::::
/sys/class/dmi/id/board_serial
::::::::::::::
To be filled by O.E.M.
::::::::::::::
/sys/class/dmi/id/uevent
::::::::::::::
MODALIAS=dmi:bvnAmericanMegatrendsInc.:bvr4.6.5:bd06/06/2013:svnNETGEAR:pnReadyNAS516:pvr06/06/2013ReadyNAS-516V1.0:rvnNETGEAR:rnReadyNAS516:rvrTobefilledbyO.E.M.:cvnNETGEAR:ct3:cvrToBeFilledByO.E.M.:
::::::::::::::
/sys/class/dmi/id/chassis_asset_tag
::::::::::::::
To Be Filled By O.E.M.
::::::::::::::
/sys/class/dmi/id/chassis_type
::::::::::::::
3
::::::::::::::
/sys/class/dmi/id/board_vendor
::::::::::::::
NETGEAR
::::::::::::::
/sys/class/dmi/id/board_version
::::::::::::::
To be filled by O.E.M.