For some reason whenever the Mac Mini goes to sleep, it takes about 15-20 seconds for it to wake up. I can think of only a few reasons for this: I'm using a PS/2 mouse and keyboard, connected via an adapter to a single USB port. Works fine, but I'm not sure if this type of set up could cause sleep related issues. I'm using an 19 inch HP monitor (model w1907) connected via an HDMI to DVI adapter. I've read elsewhere that certain adapters can cause the issues I'm seeing (specifically the Mini DisplayPort to Dual-Link DVI Adapter) but none regarding this one that came with the Mac Mini. Does seem like more than a coincidence though, especially because the monitor randomly flickers on occasion (it will black out for a 2-3 seconds, then come right back.) I'm using a an old MyBook external hard drive (connected via USB). It had a tendency to disappear in Windows due to a lack of power, so it could be related as well . Anyone experienced this issue before with a similar setup and found a resolution?