Hello !
Thanks a lot for your answer !
I bought the computer with the SSD already in but I can’t remember if it was working… But when I put the USB key with windows installation the SSD doesn’t show up.
Yes I have the last BIOS update from the MSI website.
In BBs properties it doesn’t appear, I took some pictures 
In advanced page I don’t see no words like NVME anywhere
I’ll buy a USB adaptor I think to test it ! Something like this is it ok?
https://www.amazon.fr/NVMe-PCIe-Bo%C3%AE…o+usb+pcie+nvme
Anyway Thanks again ! 
