Is it okay to leave my MacBook running overnight? Like, plugged in, screensaver? Are MacBooks meant to be run for long periods of time? (Say, a month without turning it off) I kept my iMac on for 2 years straight and it was just fine. The reason I want to leave it on is so I can rip DVDs, or download torrents overnight so their ready in the morning. Is it okay to do this?