PCIe Gen 4 vs Gen 3: Do you need to spend extra on SSDs?

NVMe Gen 3 vs NVMe Gen 4, Crucial P5 Plus 2TB Gen 4 nvme gen 4 in gen 3 slot Supported CPU: Ryzen 3rd Gen and 4th Gen processors · Supported RAM: 2x DIMM, DDR4 4933+ · Graphics Output: 1 x HDMI, 1 x VGA Port · Features: 1 x Slot, nvme m2 slot laptop For example I have two SSD bays the first one supports Gen 3 x 4 speeds the second one only supports Gen 3 x 2 speeds because there are a

nvme pcie 40 in 30 slot Solved: Does installing gen4 NVMe SSD on PCIe 3 slot affect the speed? or should i buy 3 gen3 NVMe ssd? Please give me some advice