Old SATA drives recognized in BIOS

Hello,

I recently acquired two old SATA drives from a pal of mine with a ton of videos, pictures, documents etc. on them, all of which I'm looking to keep.
I connected them through the SATA ports on my motherboard and am looking to access them directly and use them for storage. Neither of them have an OS installed, as far as I know. I would prefer not to format them and lose all the files, but I will if that's the only way I can use them.
Here's my situation so far:
They DO appear in BIOS menu.
They DO appear under my disk drives in the Device Manager , however
they DO NOT appear under Computer Management->Storage->Disk Management
and They DO NOT appear in My Computer or Explorer at all.

Any info on how to access these guys would be much appreciated.
Thanks