takes forever to wake from sleep and/or screen saver since clean install of El Capitan.

[djserrone]

iMac 27 inch i7 takes forever to wake from sleep and/or screen saver since clean install of El Capitan.

 

[bigbren47]

Same here! Brand new iMac 27" and El Capitan seems to take too long to waken up. Screen goes black with a small fuzzy square in the top left hand corner. After a few clicks on the keyboard it eventually wakens up-not happy!