When my heating has been on and the rooms are warm, I switch my PC on and it doesn't make a loud rattling sound.
When my heating has been off, the rooms are cold. I switch my PC on and the loud whirring sound is there. I have to leave it running for a few minutes before shutting it down completely. When I reboot it back up, the whirring sound goes, like something inside the tower has warmed up enough.
What could possibly be cold enough to start whirring? It only ever happens when the room is really cold.
Any info much appreciated