It's a common gaffe by owners so don't feel bad. Many monitors do that if there is no signal.
Also, many desktops start the fans at top speed until they boot. It's a safety decision to keep a crashed machine from overheating. (still not getting down to anything wrong yet!)
As to the battery, what Volts did it read? Or try another. You left out the exact age of the machine, battery and model details. Be sure to retry without any USB devices plugged in.
When ever i turn on my lenavo pc it makes really loud noise from the fan i havnt used the pc in about 2 years so it went into power saving mode but i dont i cant just turn on my pc the monitor stayes blanc and when i turn off my monitor and turn it back on it is green for a few seconds and then goes orange i took the lithium battery out and it turned on for a a few minuites and then turned off