Hey there, on all my previous Macs I've been using the upper right corner for a quick "screen off". Whenever the computer was on to some task, that took a while longer to accomplish - top right corner, screen off (which is different from brightness all the way down) to save battery. Now with the 2013 MBA it seems like for some reason (and seemingly not always) the computer itself goes into some sort of sleep mode - it stops uploads and downloads for no apparent reason (and as I said not always). I want my plain and simple "Screen off" back - if I wanted the computer to sleep, i'd shut the lid. Can anybody help? PLease?