Hi, first posting here. I use my MP for photo work (Photoshop, NX-D, etc. No video editing). I am in the process of upgrading my MP 3.1 after the stock Radeon 2600 said goodnight. - I've installed a new graphics card (ASUS Nvidia GT 610) which when installed with the latest driver works like a charm with dual display (two 24" Dells). No boot screen, but as I don't want to risk anything by flashing an EFI to it I can live with that. - I added a NANOtech USB 3 PCIe unit which works as promised. - I got a PCIe Accelsior S adapter from OWC and a Samsung 850 EVO 250GB to complete the set. Now to the issue: After using Disk Utility to format the SSD (OS X Extended Journal, GUID), my MP only recognizes the 850 as an external drive. Is it a firmware issue or is there a trick I don't know about?