One idea to always go back to is:
Extraordinary claims require extraordinary evidence
- Carl Sagan
This can be tough to evaluate sometimes, but it’s a good general idea.
Does the claim sit outside the natural world as currently understood by scientific theory?
If yes, then there’s going to need to be a lot of evidence. If not, the level of evidence is lower.
Does the claim involve a low probability event?
If yes, then more evidence is needed of that event.
Does the claimant have a stake in the claim?
For example, does the person get money, fame or other stuff by getting people to believe the claim? If so, more evidence should be required.
What type of evidence would you expect to see, if the claim were correct?
When things exist, they tend to leave evidence of their existence. Bones, ruins, written records, etc. If someone says something exists, or used to exist, but they should have archeological/anthropological evidence to back it up.
Sure, it’s always going to be a bit subjective as to what requires proof. And for a lot of low stakes things, there’s no point in going after it. If someone claims to be from Pitcairn, then what’s the point of questioning it? Just say, “huh, cool” and move on. If someone is trying to convince you that an historical figure existed, and that should effect how you see the world, maybe ask for as bit more evidence.
That’s a common indication that the CMOS battery is dead.
If you open up the system and look around the motherboard, there should be a coin cell battery in a holder somewhere on the board. That battery keeps the BIOS powered and prevents it from losing it settings when the system is powered off. Test and replace that battery if it’s dead.