I have a similar problem trying to install a Samsung EVO 850 SSD in my Macbook Pro early 2011. The guys at the apple store told me to install the new drive, hold down cmd R to go into recovery mode, then install a new OS on the drive. However when I got to that point it didnt't recognize the SSD. So I used disk utility to erase the SSD, then it recognized the drive & it let me download Mountain Lion from the internet which seemed to go well. Then I tried to restore from Time Machine which also went well. However, when it was done it wouldn't recognize my password. I tried restarting & now it get the Apple symbol & the spinning wheel. I also have an iMac. Should I try formatting the SSD as an external drive as described above? Thanks for your help!