Theoretically, there is no difference, they are both x4 PCIe gen 3. However, there are a few factors that can affect performance. CPU attach vs PCH attach. Lower power thresholds on M.2. And thermal differences. As well, the physical size of M.2 may limit the number of channels the controller supports. Rob On Mar 10, 2020, at 11:03 AM, Mauricio Tavares <raubvogel@xxxxxxxxx> wrote: This might be a bit off-topic, but what is the difference performance between those two as far as the nvme drives are concerned? All I know is I see M.2 being used for customer/prosumer-level stuff while the U.2 in enterprisy drives (ok boot disks in the servers might be M.2 but you get my drift).
