SATAExpress Vs M.2 and the whole

I was one of the unfortunate souls that purchased my motherboard ( ASUS Z97-WS ) at a time when the future of SATA and PCIe used for data transfer speeds was in it’s infant state. ASUS was going with that crazy socket that had two SATA 6 Gb ports along side another type of connection, I don’t know what it was called but all 3 together was called the SATAExpress. Now my board has a M.2 PCIe Slot_3 that is tied to the SATAExpress and should provide a X2 lane bandwidth to the PCIe . I am confused because I can’t find the clear answer as to what type of M.2 drive is going to work in that slot. I know ASUS has support for NVMe on Z97 board now but do I still need to look for a SATA M.2 drive or can I now use a NVMe drive in that slot. I am pretty sure if I did install a compatible drive in there I would still only get the 2X speeds but I’m ok with that it’s still better than 6Gbs. I would only be using that drive for storage and not the OS.

According to the Asus spec page for the Z97-WS, the M.2 is as follows:

1 x M.2 Socket 3, , with M Key, type 2260/2280 storage devices support (both SATA & PCIE mode)

so the slot will support either sata or NVMe drives in that slot, either at roughly 550Mbps~ for sata or 700Mbps~ for Pcie. I’m a big proponent of NVMe but in that slot, the difference is really meh unless you’re wanting to benefit from the faster speeds NVMe offers when it comes to transfering lots of very small files.


If you’re going to buy an NVMe drive, buy a Pcie to M.2 adapter and throw it in your second pcie x16 slot on your motherboard. Your motherboard has some a special sauce chip that generates more Pcie than your cpu natively has, meaning you can run that NVMe drive in your second or third PCIE X16 slot without losing any bandwidth to your graphics card (assuming its the only other PCIE device in a X16 lane and is in the top slot).

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I already have the PCIe M.2 adapter card to place the new Samsung 960 Pro 512 Gb drive I ordered from B&H Photo. It hasn’t arrived as of yet but I plan to put it in one of those PCIe X16 slots and run the OS from it. I want to get a 1T M.2 to stick in the M.2 slot on the board for storage. Your right, the difference in speed is meh but it’s better than 5 or 6 Gbs when using the SATA connections. Cost per Gig is not my concern. I just needed to make sure which protocol to get. I would use SATA SSD’s but I don’t want the cabling unless someone can give me a good reason to not have the drive on the motherboard.

If you’re not concerned with cost per GB than there isn’t a reason to not buy an NVMe drive for that slot, there also just isn’t a good reason for buying an NVMe drive either. The random performance will be better (real world impact? more than likely no for a storage drive on a desktop) and sequential speeds will be better although not at the full speed of the drive.

Basically you’re at a point where you can buy SATA or NVMe for that slot, and if you don’t care that you’ll be spending a good bit more for an NVMe drive, then go for it.

You can also buy a good NVMe drive now with PC upgrades in mind.

Sure you probably won’t get the speed benefits now, but if you’re upgrading to a new PC down the line you have a sweet NVMe drive already. SATA would be almost a waste there :confused: