Re: LSI SAS 3444E support on ASRock B75 Pro3
First up, I do not have this board/controller card combo.
Having said that, I have placed SuperMicro AOC-USASLP-L8i and IBM M1015 ServeRAID(LSI 9220-8i/9240-8i) in slots designated for video cards. I currently have M1015 cards running in my media server and have placed them into 939 boards vid card slots too
Items I don't see you've enumerated upon in previous posts here that might have bearing:
In looking over your manual have you gone into the BIOS's "North Bridge Config" and changed the default for "Primary Graphics Adapter" from PCIe Express to Onboard? Or even change to PCI? That advice is made assuming you're attempting two PCIe x8 cards in the only two PCIe slots the motherboard has. That leaves Onboard or PCI video. Or none for that matter if you've got it setup and running and just Remote Desktop into it via the network.
Also, you might even try changing the "PCIE1 Link Speed" to x8 if allowed.
Or possibly any combination of the above suggestions.
Other items in that BIOS that in browsing the manual that might be of interest are "Intel(R) Rapid Start Technology"(I'd set this to Disabled), "ACPI HPET Table"(Might play tough with this set to the default of Enabled) and "PCI ROM Priority"(Not sure if might cause issue or not on this motherboard, nor what settings are available)
Good luck and keep posting updates.
Mine: ASRock Z77 Extreme6, i7-3770K, 16GB Samsung MV-3V4G3D/US, SeaSonic X-750 Gold, On-die HD 4000, Corsair H80i, Antec Spot Cool, Fractal Design R4 Black Pearl w/Window
Hers: ASRock 990FX Extreme4, FX-8150, 32GB AMD/Patriot AE316G1601U2K, SeaSonic X-750 Gold, Asus HD7770-2GD5, Corsair H80i, Antec Spot Cool, Fractal Design R4 Black Pearl w/Window
Server: Gigabyte GA-990FXA-UD5, FX-4170, 32GB AMD/Patriot AE316G1601U2K, Enermax ELT500AWT, IBM ServeRAID M1015, Sapphire Ultimate HD 4670, Norco RPC-470