Does anyone know if I can buy a SATA M.2 SSD and use it on PCIe slot with an M.2 to PCIe adapter? I am looking to upgrade my x58 SLI3 and I would like to use an M.2 SSD so I can get rid of the SATA cables and drive bays.

quadlatte
Yes, they do make them. From what i gather though only certain drives are bootable.

Would they work on X58? The pcie to m.2 adapter i have is a simple passthrough, no controllers onboard to present a sata connection on the pcie, unless such controller is already part of the sata ssd.
Alternatively what are the m.2 ahci options out there apart from the 950? I can't find anything that is not nvme or sata.

timmyboy04
SM951?

which is basically the 950 OEM version. It's already an old drive and the 960 doesn't support AHCI anymore. I don't understand why nobody apart from samsung is making AHCI M.2 and them are now dropping it.

you are mixing up SATA with AHCI.
SATA drives are going up to 6Gbps. AHCI are basically NVME with a SATA OPROM to help the BIOS see them as a boot device and they can go up to several GB/s like the normal NVME drives.
Crucial makes good old SATA drives with an M.2 connection. That's fine for devices that have a SATA controller and an M.2 slot attached to that SATA controller (like many laptops). I have the feeling that if you plug in a SATA M.2 device directly to a PCIE slot with an M.2 to PCIE adapter, the mobo won't even see it as a drive and neither will the OS. PCIE does not speak SATA so the drive would need to have its own SATA controller on it. Do you know if that's the case with Crucial?