Hi to all! First of all sorry for my bad english. The help I requested for concerns the fact I'dlike to install OS on a new SSD NVMe type onto an old system Windows 7 x64 based:
MB: Asus PT Deluxe v 2.0
CPU: Intel I7 920 @ to 4,3GHz
RAM: 24GB
VIDEO CARDS: Zotac RTX 3070 + MSI GTX1080
HDD: 2 WD in RAID mode with OS onto them and a little size 2,5" SSD for SWAP file... a new SSD Nvme M.2 Samsung 980 that is not seen by BIOS
PCIe x4 Adapter used for the NVMe SSD
I updated the BIOS to the latest version. But the sSd is not seen

For sure I'm not enough expert to solve the problem, but I'd like to try with your helps.
I read some pages about a thread where I found new therms and solutions like DUET for (BIOS to EFI), EFI BOOT, Clover, AIO... but I'd really need to understand how to move with right order and First of all is it possible to solve my problem.
If is not possible on this system I could try onto other two PCs if are better or simple solutions respect this PC I mentioned.
one with CPU intel i7 970 onto a Gygabyte x58A-UD3R, 24Gb RAM...
another with I7 3930k onto a P9X79WS, 32 GB RAM...
Thanks in advance

Edit by Fernando: Thread moved into the better matching Sub-Forum and thread title specified

Ur motherboard uses Legacy bios, not UEFI so a bios mod is not possible, the alternatives u already found:
"...I found new therms and solutions like DUET for (BIOS to EFI), EFI BOOT, Clover, AIO..."

But in the P9X79 its possible a bios mod with NVMe as the motherboard is already UEFI.
In this case go here: [HowTo] Get full NVMe support for all Systems with an AMI UEFI BIOS