Yesterday I setup and configured my rMBP as a desktop replacement in my bedroom office. It had the lid closed, but it was connected to a Thunderbolt Display, which in turn had a USB Keyboard, Mouse and Lacie TB 2Big Drive attached. All night long, once every hour (I know because it woke me up and I checked the clock, very annoying, sleep deprived...) my Lacie would wake up, the drives would spin up and the very bright blue LED would turn on, waking me up. After 8 seconds or so it would shut down and go back to sleep. I wish I could go back to sleep that easily... Anyway, as I had installed the PowerNap upgrade a week ago, I thought this might be a symptom of that feature. However, I thought the concept of PowerNap was to only use flash and avoid anything that would alert the user that it was awake (like turning on fans, mechanical HDs, etc). Am I mistaken, will external hard dives always wake during a PNap state, or does this sound like it is not working as intended? For tonight I have disabled PNap entirely, but I'd love to find a way to suppress the external drive awakening. One other thought I had was about a little Lacie utility, "Raid Monitor" that runs in the top right menu bar. It just reports if there is a drive issue. Perhaps that process gets run during a nap wake cycle and it stats the drive causing a wake, and then the whole machine sleeps again 8 seconds later? I suppose I could try disabling that utility too. Or perhaps this issue has nothing to do with PNap? Has anyone else experienced anything like this? Thanks for any info!