The computer won't turn on when it's cold.

The weather is too cold, and the condensation of water vapor leads to poor contact at the switch. Press it a few times more, as long as it runs smoothly, it will be ok.

See if there is a switch contact problem. You just need to open the case, find the wire connecting the switch, unplug it from the motherboard, and point it on the connector of the motherboard with a bottle opener. If you can turn it on once, it means that the switch of your chassis is in poor contact and will not affect the use.

The noise is too loud because water vapor condenses on the rotating shaft of the fan. As long as the temperature is not low, it is ok. The computer has a most suitable temperature range, generally not too low. Put a roast foot next to the computer, kill two birds with one stone.

As long as it does not affect the use, these problems are not big! But the temperature is low, and I don't need a computer for a long time (more than a week). Before use, it is best to open the case, dry the water with a hair dryer and then turn it on.