SC48 Error & Crash mid-show

[Mixsmasha]

SC48 displayed 'Ready To Resume" dialogue on screen mid-show. (see attached)
Selected "Resume Operations" command.
Desk then went into fault mode with all meters at max level and high frequency screech.
Restart was slow and then a song or 2 later, same 'Ready To Resume' error appeared - desk then went in 'Backup mode' - only mutes and faders working.

Tried a second restart - this time appears to cycle around a fault in the BIOS boot-up - never fully loading to startup screen - this repeated for 5-6 minutes.
Unable to enter Test mode.

Thankfully had another Sc48 in the truck and swapped out (phew!).

Appreciate any insights into potential cause.
•Hard Drive?
•Motherboard?
•BIOS Battery?
•RAM?

Thanks for any insights.