If it's not one thing it's another. So I've had a HighPoint RocketRaid 622 eSata PCIe card installed for a while now and it has worked flawlessly with Mavericks. However, now with Yosemite installed it is sadly no longer support by the OS. I went ahead and purchased the new HighPoint Rocket 644L which is compatible with Yosemite. When the 644L and Velocity Solo x2 are both installed the system does not boot off the SSD. I remove the 644L and it boots fine. I tried rearranging the order in which the PCIe cards are installed and although there were some changes, it still does not function properly. Any help is greatly appreciated. With all the PCIe issues I've been having, I'm really starting to consider buying a nMacPro. Specs: MacPro5.1 OSX 10.10.1 Intel Xeon W3690 Hex-Core 3x8GB (24GB) 1333 RAM 802.11ac & Bluetooth 4.0 (MacVidCards upgrade) PCIe: (Original configuration) 4) Rocket 644L eSata 3) Apricorn Velocity Solo x2 + 1TB Samsung EVO 840 2) Inateck KT-4004 USB 3.0 1) EVGA 4GB GTX 680 FTW (Mac ROM) Other Hardware involved: SansDigital eSata 4bay JOBD EDIT: Found out I actually have the Rocket 644L (not RocketRaid), which does not have the Web GUI. EDIT-II: I purchased a RocketRaid 644L but I can't access the WebGui.