M2 PCIe issue

I'm on the process of building my new system and have found an issue. The have a X99 Extreme4/3.1 board and have installed a Samsung SM951 M.2 PCIe 3.0 (x4) NVMe SSD. I've not installed the OS yet because the drive is not listed under M2, but under SATA. How can I be sure the drive is running via PCIe and not SATA?

gareth_alien wrote: I'm on the process of building my new system and have found an issue. The have a X99 Extreme4/3.1 board and have installed a Samsung SM951 M.2 PCIe 3.0 (x4) NVMe SSD. I've not installed the OS yet because the drive is not listed under M2, but under SATA. How can I be sure the drive is running via PCIe and not SATA?

I assume you have your NVMe SM951 installed in the Ultra M.2 port, or possibly an M.2 to PCIe adapter card?

Either way, it is impossible for an NVMe SM951 to be using the SATA interface. All SM951s have the equivalent of a storage controller on the SSD, whether NVMe or AHCI, and do not use the board's SATA controller.

If you are seeing your SM951 listed among the SATA drives, that is probably related to this, from your board's specifications:

S_SATA3_2 connector is shared with Ultra M.2 Socket

Intel allows some of the PCIe resources on your board to be configured for different purposes. Your board shares resources between the Ultra M.2 port and the S_SATA3_2 port. The Storage Configuration screen in the UEFI may even have an option to select which port will be assigned to those resources. Do you have a SATA drive connected to the S_SATA3_2 port?

Do you see your SM951 listed in the S_SATA3_2 line in Storage Configuration?

What OS is installed in the PC you have the SM951 in now? Did you install an NVMe driver for your SM951?

Don't expect an NVMe SSD to be recognized in a board's UEFI in the same way as SATA drives are. They don't even appear in the M.2 port list in the UEFI on the latest Intel boards.

You can be sure your drive is using the PCIe NVMe interface, by running a benchmark like AS SSD.