M2 SSD Compatability

Hi parsec,

Thanks for clearing up my misconception about the lane allocations. ++

Re: MBR

I manually specified MBR using GParted to sidestep any UEFI and GTP friction with the OS installer. The UEFI is set in compatibility mode, so it was smooth.

Re: 750 Ti

I also have a bootable OCZ Vertex 4 on the system.. in running OS in that device with the vids stored on the NVMe 950 Pro... there was no stuttering.

In that config the vids and 750 are served up on PCIe..   

So some of the workload went onto the  Vertex 4 SATA  bus for some reason...
Video driver and GPU+CPU may have transactions with temp files outside memory while doing these tasks.

Re: NVMe driver

It's been a native Linux kernel driver since kernel version 3.3 (18 March 2012)
I'm running 4.4 version right now.  You can imagine my impatience waiting for mobo houses to bring it to the BIOS/UEFI but that's an 'ecosystem' thing, do you think?.
Anyway,  that stuff I said about fluffware and NVMe vs SATA.. that was BS in retrospect, that's my fault,  it's actually a few of the  higher level GUI apps that are lagging a little with ability to display storage device Mfgr/Model etc.

 Using the lsblk command ( List block devices),   the correct info was displayed in the terminal  for the NVMe based 950 Pro
aside: lsblk command at the bottom of the page...
http://fibrevillage.com/storage/53-lsblk-command-examples

HI Crazynex,  parsec, Xalter and Phillium.
So,  I appreciate the stuff I read on this thread.. good advice and info. 
I got the Samsung 950 Pro running with only one or two hiccups that were  dealt with.


Rig:

ASRock Fatal1ty 990FX Killer, BIOS P1.60 01/06/2016
AMD FX(tm)-8150 Eight-Core Processor (family: 0x15, model: 0x1, stepping: 0x2)
ASUS Hyper M.2 X4  (PCIe to M.2 adapter card)
Samsung 950 Pro
Operating System:    Ubuntu 16.04.1 LTS

First, installing Ubuntu 16.04 to the 950 Pro in the mobo M.2 connector went with one hiccup. NO MBR on the device.. but no messages to indicate that. So, briefly,  I did the install there (X2), but later got the ASUS PCIe  to M.2 adapter card and redid the whole install there.

So following the advice I found  on the web:

• Before the install of the OS, first create an MBR and a partition on the device.. and a file system (I chose ext4) , possibly use GParted Live, or GParted in another linux computer..
  
•  
• Install the OS, cautious people unplug other SATA devices,  I hear.
  
• choose the option 'Install to Other' which allows you to look at the devices on your system and pick the right one.
• Select the partition and mark it as the root of the file system.
• 
  
• When installing, install to the device, not the partition.. something to do with where the GRUB2 bootloader ends up maybe. So select the device.. like mine was  device nvme0n1 and the partition was nvme0n1p1.
  
• Then follow the menus.

So, benchmarks show that I'm using PCIe version 2 in the results... but I still like them and I can move the 950 Pro to my new machine when I upgrade..   like ASRock  ZEN FX mobos  this Christmas?.  I'm dreaming..

  so Benchmarks.. as they are, are here: http://imgur.com/a/NjGKb

PCIe 3.0 would be faster.

So I'm also running an Nvidia GX 750 Ti mid level graphics card. I noticed that if I run 4 HD 1080p movies at once in different VLC windows, , when I load a 4K movie on top of that,  it gets choppy. Hard times! So that's when the SSD competes with the graphics card for bandwidth on the PCIe 2.0 bus, doing these tasks.

Comments on the state of Ubuntu w.r.t. the device: it works.. but I notice that that benchmark pic doesn't show the device manufacturer nor the model. So, NVME works.. but some of the fluff software that exists for SATA isn't aware or can't use the NVME interface to get that info... today.. August 25, 2016.   : )

I agree, and you're not the only one that was confused or possibly provided misinformation about the SM951.

It was never meant to be sold at retail. You can't find it listed among Samsung's SSD product information, whether AHCI or NVMe. It's not really supported by the Samsung Magician software.

But, the AHCI SM951 can be used in boards that don't have NVMe support. It also is a very fast SSD, still among the fastest SSDs available.

NVMe support is very new to AMD boards, and is new on Intel boards too. I would like to see for myself how good the NVMe support really is on AMD boards.

I have a Fatal1ty 970 Performance/3.1 board that has a UEFI update for NVMe support, so I'll give it a try. Not full support for PCIe 3.0 x4 NVMe SSDs, but they should work.

This is what a 256GB AHCI SM951 does with a full PCIe 3.0 x4 interface. I would hardly call this bad compared to the NVMe SM951 or 950 Pro:



A 256GB 950 Pro on the same mother board:



This simple benchmark does not tell the entire story about either SSD's performance, but they aren't that much different in the basic performance aspects. Both of our AMD boards can't match the bandwidth on this (latest generation) Intel board, but it will be faster than any SATA SSD on our boards. I've had no problems with my AHCI SM951, I think its great.

Phillium wrote: I'm having a similar issue with my SM951 (UEFI version 1.6) where I cant get the motherboard to set it up as NVME, it only registers AHCI and i cant even find where in the UEFI I might change that, as the system overview has little information and zero functionlity, and theres no M.2 labled functions.

I'm assuming the same mother board as the OP, the Fatal1ty 990FX Killer?

FYI, the first and much more common version (of an overall rare SSD) of the SM951 SSD is an AHCI type of PCIe SSD. I own two of them.

You own an AHCI SM951 too, given what you have described.

The model number of the AHCI version of the SM951 is MZHPV256HDGL, for the 256GB version.

The model number of the NVMe version of the SM951 is MZVPV256HDGL.

The model number is on the sticker of your drive, or can be read by various software. It should show up in Device Manager like this:



You can also see how an NVMe SSD is listed in Device Manager, and the entries for their controllers, both AHCI and NVMe. The correct driver for each type of SSD is loaded automatically.

The NVMe version of the SM951 was available for a short while before the first Samsung M.2 NVMe SSD meant to be sold at the retail level was released, the Samsung 950 Pro.

While the SM951 SSDs in AHCI and NVMe models use identical SSD controllers, the firmware each one has is different, and is what makes the SSDs either AHCI or NVMe.

There is nothing in any mother board's UEFI that can change an SM951 from AHCI to NVMe. That is solely based on the drive's firmware.

How can you change the firmware? You can't. Samsung would need to provide that, and they don't. The SM951 is not supported by the Samsung Magician software, which is where firmware updates can be done with supported Samsung SSDs.

We are very lucky that ANY AMD chipset board, particularly the old 990/SB950 pair used in your board, can support any PCIe M.2 SSD, AHCI or NVMe.

The latest Intel boards that support PCIe M.2 NMVe SSDs do not have any additional functionality either. That Intel chipset is far beyond the AMD 990/SB950, and actually provides the full bandwidth required by an SM951 or 950 Pro (PCIe 3.0 x4).

We are lucky that we can use SSDs on the same physical interface (M.2), while they use different protocols. If you expect them to be the same as SATA drives in the UEFI, then you will be disappointed.

2 PCIe 2.0 lanes is roughly a quarter of the bandwidth of 4 PCIe 3.0 lanes. Basically PCIe 3.0 x1 = PCIe 2.0 x2. Now the question is, does the M.2 SSD saturate the full PCIe 3.0 x4 bandwidth, if so then it's peek performance will be bottlenecked by 75% on a PCIe 2.0 x2 interface.