NVMe Support for Asus Rampage II X58 with RAID and Samsung 950 Pro

Hello everyone,
I cannot enable built-in Intel SATA RAID on my Rampage II or the BIOS fails to recognize my 950 Pro is bootable while my RAID1 SSDs are connected. When I just unplug these i can boot Win 10 directly from Samsung 950 Pro via NVME/Pcie adapter while NO other RAID1 SSDs are connected (BIOS MODE is stil: RAID). When I switch to AHCI the Raid dissapears and also everything boots up.

I don´t wanna miss my semi hardware BIOS Raid. Is there any chance to use Clover or Duet from USB Stick to boot my existing Samsung 950 Pro WHILE RAID keeps active in BIOS and these SSDs are connected?

Kind Regards

Stefan

Specs:
Asus Rampage II Extreme, Chipset Intel X58 Modded Bios and Meltdown/Spectre Microcode patch
Intel W3680 OC to 4.4Ghz LC
24GB DDR3 RAM
1x NVME 500GB Samsung 950 Pro M2 SSD with cheap PCI Express adapter 4 lanes 2.0
2x SSD Samsung 750 EVO RAID1
2x SSD Samsung 860 EVO RAID1
2x SSD Samsung 750 EVO RAID0
1x GIGABYTE GeForce RTX 3070