I successfully Flash my BIOS with the two modded ones available on this post:
So I thought OK I can try this out and bought an EVO 970 PLUS plugged in a 1x slot SABRENT PCIe interface
Thanks to @shawn I’ve decided to migrate my existing Win7 OS from MBR to GPT
So I did install the Windows6.1-KB2990941-x64.msu to see the MVMe in Win7 + cloned my system with AOMEI BackUp with option convert MBR to GPT
At BIOS boot menu I was able see the EVO 970 PLUS but without being able to reboot on it:
Eventually I used AOMEI Partition Assistant Pro to convert my SATA system from MBR to GPT with the intention of cloning after reboot.
But I can not reboot anymore
I must have miss something…
Thanks for your help!