Hello, I have a late 2011 macbook pro and about six or so months ago I have it a new lease on live with a Samsung 840 SSD (non pro), and an optibay for the hard drive. I haven't really had any problems with that until recently - the machine started locking up on wakeup. This meant that the beachball of doom would start and each program would gradually in turn become unresponsive. Shutdown command wouldn't work and would time out, force quit wouldn't open, and although I could move the mouse around and sometimes switch between programs, they didn't work and the only cure was to hold the power button until it switched off. This has also started happening just when the computer has been on for a certain amount of time *without sleeping*. For example, if I watch an episode of a tv show, by the end of it the video is still running but all of the other programs are locked up - clicking out of VLC causes the beachball of doom. This also happens in other programs - it's even happened as I've been writing this, and the only remedy seems to be a hard restart. The problem doesn't seem to occur in windows. In OSX I have 'put hard drives to sleep' turned off, and TRIM enabled. I also disables the sudden movement sensor. I have also reset the SMC. Does anyone know of a remedy short of a full reinstall of Mountain Lion? Oh and I used samsung magician in windows to update the firmware of the drive. It reports that the drive should be fine. Thanks very much for any help anyone can give me with this!