Mac Insomnia

I have troubleshoot beyond the average user expectations, google for answers and read many forums posts to no avail... and I refuse to believe that I will have to download a 3rd party app to make my iMac go to sleep.

My MacBook has shown similar symptoms but in that particular aspect I've observed that closing the lid does induce system sleep, but the biggest problem is worrying that my iMac will stay up for days.

At the beginning I concluded that this insomnia was due to the Widget screen being up; but then I realized leaving Safari open will not allow the computer to go to sleep. Recently, I made a new partition for Bootcamp and removed and reinstalled some software --including reinstalling OS X; then I realized that with no Apps running (even after a reboot), bluetooth disabled, USB printer shutoff, no network wake, FileSync not running, etc., the display will sleep as specified in the Power Management options, but it will not go into system sleep.

There has to be a way I can at least tell what process is not allowing this, but there has to be a fix for this --this shouldn't be this complicated.