I'm losing my mind here. I recently got a 2011 15" macbook pro. Installed a 2nd HDD in the optical slot. I took this from my old MBP where I had no issues using it. My setup was SSD in HD space. HDD in optical space. Anyway, I installed it in the same configuration described above and I've had nothing but problems since. If I have ANY drive installed in the optical slot, the computer is extremely slow. It boots slow, the login screen is laggy, opening disk utility results in a spinning beachball. Once I disconnect the 2nd HDD, the computer is back to normal. Also, I can hook any of these drives up via USB and access or format them. Here's what I've tried so far; -3 Different HDD's (Same result, verified working) -New optical cable (No Difference) -Put SSD in optical & HDD in HDD slot (No Difference) - NVRAM reset (No Difference) -Reinstalled optical drive (works fine) -Put HDD caddy back in 09 MBP (works fine) -Booted from USB to access Disk Utility (beachball) My next step is to purchase another HDD caddy, I just don't see how that could be the issue since it works fine in my other MBP. SOMEONE PLEASE HELP! SO FRUSTRATED!