I took my 2014 2,6 Mini to a local repair shop today to have them fit a new 500gb Samsung 850 EVO SSD. They have returned it tonight but the machine takes over 30 seconds to boot. My 2012 2.5 mini had an older 64gb SSD and that booted in about 13 seconds. This new SSD when turning on sits on a black screen for 20 seconds before finally displaying apple logo and then taking 10 further seconds to load the main screen. Do i have an issue? Why is it sat on a black screen pre apple logo?