My brother have a MBP (mid 2012). He recently updated it to Yosemite. It was very slow, and every time he closed the lid, it wouldn't go to sleep. Instead it would become very hot with the fans running, but with nothing all programs closed on the mac. He did a clean install twice. It took like 5-6 hours to install, it was still very slow, and still wouldn't go to sleep after the lid was closed. It should be said I have a MBP (early 2011) with Yosemite, and mine was a lot quicker even though his model is a lot better than mine. Downgraded to Mavericks. Again took like 5-6 hours to install. It isn't slow anymore, but it still won't go to sleep when the lid is closed. Wake for Network Acces has been disabled every time, but with no luck at all. Something that happens often is that when you close the lid, and wait maybe like 2-3 minutes and it still hasn't go to sleep, when you open the lid again it instantly goes to sleep. Then 10 seconds later or so it wakes up again by itself. I have taken the Apple Hardware Test, but it said everything was fine. I think something is wrong, because Yosemite was so slow, it took forever to install Mavericks and Yosemite, and it won't go to sleep. Thought it maybe was the harddrive og harddrive cable, but since Mavericks is running just fine, I don't think that's the case. Anyone got a clues what's going on?