[Request] Asus R510LB (X550LB motherboard) BIOS unlock

Hi there,

I have Asus R510LB (X550LB motherboard). Recently Iv'e bought a new Intel SDD (535) for the laptop, but WIN10, WIN8.1 and Ubuntu installers don't detect the SSD for some reason.. Win7 is the only installer to detect the SSD..
The SSD working fine in two other PC's.

I think the problem is my laptop's BIOS - for some reason, there is no CSM/Secure boot/UEFI options in it... maybe because the laptop came with FreeDOS.

Can someone please unlock the BIOS for me?
this is the link for downloading the update file of the last version: http://dlcdnet.asus.com/pub/ASUS/nb/X550...BAS403.zip

Thanks.