That the CMOS battery is dead, at least if the clock has reset, that will also reset your BOIS to defaults, there may be other issues at large here, but replacing the CMOS battery is where I would start.
Samsung Galaxy S8 review
1995-2015: How technology has changed the world in 20 years
This poetic animation about monsters is illustrated in a Van Gogh painterly style
How to get WWDC 2017 tickets
Synology invites you to visit them at Insomnia on 26th – 29th August. Book your tickets now and visit Synology.