‎G15 5515 SSD Gen 4 support?

Is it okay to put Gen 3 SSD in my motherboards Gen 4 pcie slots? can you put a gen 4 ssd in a gen 3 slot Thanks to the gumstick format, SSDs have been shrinking—and getting a lot faster, too Here's how to buy the right SSD, along with deep-dive canine carnage slot Rocket 4 ssds are fast, but still not fast enough yet to max out a PCIE Gen4 M2 slot yet Samsung 980 PRO and a couple others similar to it

candy candy slot 1x SSD PCIe Gen 3x4 NVMe slot, $960 Dell XPS 13 9300 , 1x 1x 2280 NVMe Gen 3 slot + 1x 2280 Gen 4 ; 1x 2280 NVMe Gen