I am currently using Mac Pro 5.1 (2010) My configuration is 1) Apple Raid Card in PCIe slot 4 2TB bootable HDD and 3x 1TB HDDs configured to RAID 0 2) Apple Radeon 5770 card in PCIe slot 1 3) Sonnet Tempo SSD with Apple OEM 512GB SSD in PCIe slot 2 4) Caldigit Fasta-6GU3pro USB3 + eSATA card in PCIe slot 3 When I boot from 2TB bootable HDD in main slot #1, everything works well. But, when I install Mavericks to 512GB SSD in PCIe slot, installation finishes without problem, but the system NEVER boot up with that drive. (The drive appears in boot disc selection in system preference, but nothing changed even select it and reboot.) (I did a lot of PRAM reset too...) The SSD works well when I put it to 2nd ODD slot with spare SATA2 connectors in there. (boot properly, etc). But when I put it back to TEMPO card, It never appears during boot process (even I press option key). Maybe problem is due to 1) Issue with APPLE raid card 2) problem due to two additional SATA controllers in PCIe rains. 3) Issue with card configuration (I have to test change the position of cards except APPLE RAID which requires slot 4) . Does anybody experienced similar problems?