Hi everyone. First off I want to apologize in advance. This post will be long, but it should explain my issues and I could really use your HELP! The issues I have been having with my mini have dated about 3 weeks now. It all started when I would hear a random clicking/purring noise coming from the machine. Initially I wasn't positive what it was, but my initial thoughts were a hard drive problem. My fears increased when I noticed the same noise coming from the mini when my computer was put in sleep mode. This made no sense to me considering the computer shouldn't make ANY noise when it's in sleep. I figured it was an upcoming hard drive failure, and when I got around to it I was going to make the long drive to an Apple store to get it fixed. Fast forward a few days and the noises seemed to be gone. They weren't coming and going every minute like before so I thought maybe it was something random, but I still feared hard drive. That's when I decided to upgrade to Yosemite. Downloaded it on release day, downloaded quick and fast and started installation. It said it was going to take a while so I went downstairs and cooked dinner. Came back an hour or so later and I had this message/error on my screen (gray screen with "X" logo on it), "OS X could not be installed on your computer. (next line) There is not enough free space in the Core Storage Logical Volume Group for this operation. Quit the installer to restart your computer and try again." I had no idea what this meant, but I assumed this was linked to my possible hard drive problem. I tried to hit restart but couldn't, so I held down power, to shut down and reboot. Well this is when my computer started taking the crazy pills. The computer would reboot, but I would get a gray screen with a dark gray apple and a status bar that would move and then always get stuck.... So I called Apple Care. I was able to work through some things with the tech to get it booted finally, and my intention was to restore from factory and start over. Well the only thing I didn't notice when I was on the phone with him was that it was only booting into safe mode. Finally I was able to restart in safe mode, into regular mode and the computer seemed fine. Worked fast, all components were checking out, no errors in disk utility, RAM being recognized fine. So I put the computer to sleep and went about my day. Next time I went to use the computer I noticed that when woken from sleep my monitors would wake up but the computer was inoperable. I had a glow around the cursor and nothing was clickable. Hold down power, restart, boot into normal mode fine, computer snappy and good, but same thing....put into sleep mode and it bricks the computer. Called support again, and the tech feared HD and logic board issues. This is when I get HULK angry. Apple had my computer for 6 days, could never diagnose anything because they said my computer would consistently pass all of their tests. However, because of everything I was describing to them they decided to repair and replace the 5400 HD and the logic board. Got a call on a Thursday morning, picked it up that night, plugged it all in and same thing as other times. Computer would boot into Apple logo with frozen status bar. I was so TICKED OFF. How could they tell me to drive 3 hours round trip to pick up a computer they obviously had not checked or tried to boot and use? This was followed by a 4 hour call to Apple Care again, that made me run all the same tests before. Reboot to recovery, restore computer, reset pRAM, yada yada yada. Finally was able to boot into normal mode again.....but again, SAME SLEEP MODE ERROR!!!!! So here I am, with my computer back at the Apple store because the tech said, "well it could be the SSD." So they are supposedly going to replace that. Initially he kept telling me it was the user installed RAM. I went along with him by putting back in the stock apple ram with changed NOTHING. So, computer went right back, they have had for another 4.5 days now, and they again have no diagnosis. Passes "tests", but these obviously still has issues. They called me the other day asking for my iCloud password because they wanted to log in because they said it could be an error with my user account. I happily declined them because I am not giving the Apple Store access to my iCloud. They can restore the computer, boot it with a test account, and they will continually get the same errors with the sleep mode and random frozen status bars. I am waiting on a call today, because after I called again yesterday to check on status they made it sound like they were going to install a new SSD to be safe and see if that solves the issues. I am just really ticked because by the end of this all I will have spent 12 hours in my car going to and from this store, gas money, and around 7 hours of my time on the phone trying to fix my computer after they had returned it to me the first time. It sucks being without my computer considering I use it quite frequently for work when I am home, and they have had it almost 2 weeks now.... I really hope I get it back and working and that they do something to make up for this inconvenience, because it sure has been no fault of mine. Their negligence and stupidity has amazed me. Any thoughts or suggestions? Thanks in advance. I still think its a hard drive/software issue.