I’ve noticed eM Client version 7.x no longer gives up its memory usage when minimized to the taskbar as it did in version 6.x.
Once minimized in version 6.x you could see in the task manager the memory numbers dropping to as low as 6MB. It was nearly asleep but not quite, still able to show new mail notifications but it did take a few seconds for the GUI to repaint once you clicked on the taskbar icon to restore the program.