Out of curiosity, had you gone in and changed that setting at one time, or did the error report just show up out of the blue for no reason recently?
Look, I don’t know anything about BIOS other than to check for updates a couple of times during the life of the box. But it would seem to me, that unless you changed something, it’s not going to change on it’s own.
Not to belabor a point, but I think I would follow David’s advice on a backup scheme, soon. With my limited knowledge of these things, I still think your hard drive may be sending you a message.
(If my reasoning is wrong, I’d appreciate a comment. Always trying to learn something new…)