as of late with my d3 gaming, i've noticed weird circumstances where my computer would shut down completely as if someone pulled the plug. this has happened twice without any warning.

the last time was yesterday and while i was playing. i rebooted and it showed

cmos time and date not set

i don't know if this means my cmos battery is dying or my motherboard instead.

yes i know not much can be gathered from this story but what may have caused such hard reset problem?