Looking to upgrade my old Gigabyte H97M-D3H with Nvme with PCIE 2.0x4 adapter. I want to dual boot Opencore High Sierra and Windows 10.

I already have this setup on SATA SSDs but as I am performance hungry I need more speed in terms of boot and usage. Could you please suggest what would be safest nvme which I can use via only PCie 2.0x4 Lane because other slot has Graphics Card.