Ive installed a Sonnet Tempo SSD PCIe card (not the Pro version) and 2 x Samsung 840 Pro SSDs in the top slot 4 of my 2009 Mac Pro 4,1 The drives showed up as orange external type drives in the OS with eject button icons next to them in the sidebar. After formatting the drives, I cloned my OS onto one SSD using SuperDuper, and I installed a fresh OS X Mavericks onto the other SSD using the Mavericks installer. Neither of the SSDs shows up when I option-boot my Mac to the startup options window. But they both show up in System Preferences> Startup Disk, but when the machine restarts it doesnt boot from them, it just reverts to my normal 7200rpm OS drive in the SATA bay. I have downloaded and run the Tempo firmware updater MarvellFlasher. I'm not trying to RAID the drives together, just use them as 2 volumes. Any ideas why I cannot boot into one of the drives?