help on what nvme i can use

[RobTi]

Hi my son has an Asus TUF Z370-PLUS GAMING mb and would like to fit a nvme into it but i am confused about pcie speeds if they are backward compatible and what about the intel optane that really confuses me,

Intel® Z370 Chipset :
2 x M.2 Socket 3*1, , with M Key, type 2242/2260/2280 storage devices support (SATA mode & X4 PCIE mode)
Intel® Optane™ Memory Ready

so any help on what he can fit please ?
Thanks

 

[Tetras]

Z370 is PCI-E 3.0, but if you check in the datasheets, most PCI-E 4.0 drives will say they are backwards compatible.