Dear friends I have a Dell Vostro 3446 the same one mentioned this topic but I have a strange problem after rebooting the installer my system stuck at Dell logo screen with showing F2 Set up and F12 boot Option the progress bar not loading in short system fails boot in to any media (Hdd or USB) but in windows side all perfect system works normally .... system passed all diagnostic test every thing perfect there it is three year old and run El Capitan success fully .... I updated bios from A09 to A12 .... nothing help to solve the problem .... please help me