The difference between PCIE NVME & M.2 PCIE NVME?

[Dogsnapper6]

Ok I'm very confused as to what the difference between some of the SSD's I'm looking at I currently have a Samsung PM951 256GB M.2 PCIe
Gen3 x4, NVME SSD
when I look online I have just realized that the ones that plug into the actual PCIe slots have an M.2 slot with a chip plugged into them do all of the PCIe connected SSD's have this M.2 attached and which is faster if at all and by how much I currently have my M.2 configured at x4 and PCIe instead of SATA which disabled two of my SATA ports so I'm wondering if the one that plugs into a PCIe slot would also disable and SATA ports as well. One of my M.2 ports lays flat and hidden on my motherboard which is an ASUS Maximus IX Code Z270 and the other sticks out so that one is in play now bc of heat possibly being an issue and I'm also told that is another reason to choose the other kind. I wouldn't say I was a noob when it comes to all this but still have a ways to go so thank you in advance for your help.

 

[JamesSneed]

There is no functional difference as they both work over the PCIE bus and use the NVME protocol.

The SATA port disabling is simply because SATA is also run over the PCIE bus to talk to the chip set so when you connect a PCIE drive you use up some of the available PCIE lanes.

 

[Hardware Brad]

Speed and performance wise, there really isn't a difference between M.2 NVMe drives and PCIe NVMe drives, because they both use PCIe lanes. With your particular motherboard, using M.2 will disable a couple of SATA ports because the M.2 slot is sharing PCIe lanes with those SATA ports. If you were to get a PCIe SSD, it would not disable any sata ports, because the PCIe slots on your motherboard do not share lanes with any SATA ports.

 

[Eximo]

I'm not entirely sure what you are asking, so I will try to answer the individual points.

NVMe is the protocol that these device communicate on. It is intended to support faster devices.

M.2 using PCIe is a PCIe connection, usually through the PCH (chipset) on the motherboard.

An M.2 card plugged into a PCIe adapter, is still PCIe connected, so virtually no difference. The advantage here is that you could potentially get a card that accepts multiple drives and plug it into an x16 slot.

A direct PCIe SSD, which are pretty are these days, can go directly to the CPU or through the PCH depending on which PCIe slot you use. Many of these existed before NVMe was a standard, so they typically weren't capable as boot drives, but offered professionals extreme performance (at the time) compared to SATA SSDs and hard drives.

As to disabling ports, that is entirely up to your motherboard's configuration. They are all a little different, but disabling SATA ports (A typical set of two is given a single PCIe lane through the PCH) is pretty common. In other cases, you might have 3 1x PCIe slots and one 8x/16x slots. When you plug in a 4x card into the larger slot, the other three 1x slots may be disabled. Again, very board dependent.

 

[atomicWAR]

As stated there isn't much difference beside the interfaces themselves. Both achieve the same speeds when rated at the same PCIe lane count (ie PCIe 4x add-in card = M.2 with PCIe 4x).

 

[Dogsnapper6]

Ok I think I see now but I noticed that I saw some of the PCIe SSD's had the M.2 drives attached to them and some of them have covers like some of the intel versions does this mean these are all just adapters or are there 2 different kinds of those as well?

 

[geofelt]

m.2 is a size format; about the size and shape of a stick of gum.

The m.2 attachment to a motherboard can be either sata or pcie depending on the device. pcie is about 4x faster.

The add in cards plugged into a X4-X16 pcie slot will have some sort of adapter.

I would not worry much about heat.
Throttling only occurs under heavy continuous sequential operation.
A virus scan with a strong cpu might be such a situation.
It takes some 60 seconds for this to happen. No damage will occur if the ssd slows down a bit.
There are some cooling solutions out there, but it is not clear how effective they are.
Normal case cooling should suffice.