[Discussion] Performance of the Samsung M.2 SSDs (AHCI/NVMe)

Hi Win Raid Forum and Fernando as well, my first post this year and a happy new year to very one.

But the reason to open this thread is to have a wise knowledge of this new technology in which I’m interesting one and since I have learned a lot from this forum and I have read a little from other forum about this technology and I want to share this information as well have other with wise knowledge on this technology to share its experience here. I own a SX941 M.2 card gen.2 and this card have its own drive integrate on it controller in which I believe it is an NVme driver or firmware, and someone can correct me if I’m wrong. Now I seen the successor of this M.2 card which its the SM951 M.2 card and promises to deliver a better performance, but the draw back its that it needs to run with this type of driver the NVme driver or firmware without it its not capable to run at its fullest potential or performance, and if all that is true why Microsoft or Samsung it self have come out with a fix driver to have its fullest performance in Windows.

Now I ask does the XP941 use this same driver than the new SM951 gen3 M.2 card? and if it does can some one here noes how to get this driver or better yet how to make Windows 8.1 to force to recognized or load this driver while setup.

Note: here are some info about this driver: https://www.iol.unh.edu/sites/defaul…uite_v1.1b.pdf

@ Camp Anaconda:

Although I am not an expert regarding this topic, I will try to answer your questions:

  1. When you speak about a “driver” for an M.2 PCIe SSD, you certainly mean an UEFI “Driver” module, which has to be within the mainboard BIOS, because otherwise the M.2 PCIe card will not be bootable.
    So if you want to buy and to use the Samsung SM951 M.2 PCIe card for the OS, you should ask ASUS, if the required EFI module is within their BIOS for your mainboard.
  2. The upcoming AHCI successor NVMe will only work for your system, if the mainboard BIOS does support this feature. Ask your mainboard manufacturer.
    By the way: According to my knowledge the upcoming Samsung SM951 will not support NVMe. Samsung has recently given the information, that NVMe will come later. Until now nobody knows, if that means, that this feature will come to the SM951 by a later released Firmware update or that it will be implemented into the successor product.

hey Fernando thanks ones more for your promptly answer but did you read the attach pdf file, there is some info in regard now to try to install this technology using the shell setup and since I not a expert using the shell system I don’t even bother to mess with. But the XP941 use or is capable to use this driver? I now that this driver has to be within the BIOS but or I believe it can be done by MODDING the bios, and that’s where SonyX and CoderRush can come to play. I will see if CoderRush with his UEFI tool this driver if found can be insert in bios, so when setting Windows and especially Windows 10 can fix this. I’m just speculating guy something to give me to do. Peace.

I think this is the driver that ones found it needs to be insert, I think (NvmExpressDxe.x64.efi)

I cannot open the pdf file, because the link doesn’t work.

Within the BIOS of my ASRock Z97 Extreme6, which already supports the NVMe feature, I found 2 NVMe modules named "Nvme" and "NvmeSmm" and additionally a module named "Samsung_M2_DXE", which is obviously the "SataDriver" for the Samsung XP941.
After having extracted and opened the module named "Nvme", I found the text code "A.M.I. .N.V.M.e. .B.U.S. .D.r.i.v.e.r".

The name of the file is less important than its content. So I don’t know, if the file named NvmExpressDxe.x64.efi is identical with the module named “Nvme”, which is within the BIOS of my mainboard.

Ok Fernando, I’m not a guru on this guy just sending you this info for you to check and if you find any or a better way to install Windows through the UEFI shell, so let me know.
Also this link as some drivers http://www.nvmexpress.org/products/

2013-FMS-NVMe-Track.pdf (5.1 MB)

20140918_NVMe_Interop_Test_Suite_v1.1b.pdf (127 KB)

The drivers are hosted on the same page. For BIOS insertion you need the UEFI Driver, which has to be compiled. There is one compiled here, but don’t know if it is untouched. Next you need to pack it in ffs, where all OEMs seem to go for 634E8DB5-C432-43BE-A653-9CA2922CC458 GUID.

NVMe and NvmExpressDxe are doing the same thing, just that the first is AMI source, while the last is Open Source. You could try to extract Nvme from any of the board, but stay away from any *smm modules, because they are for System Management Mode.

I read some review about M.2 card before which they test if it is bootable (for plextor M.2 and samsung x941)
the Plextor M6 M.2 card can boot in all motherboard in both AHCI and UEFI mode, but the x941 only can bootup in 9 series intel chipset with UEFI.

So may be plextor include all things need to boot, but samsung didn’t?

p.s. see the motherboard compatible part.

That is correct. The Samsung XP941 needs a special EFI module within the mainboard BIOS.

hey Fernando, I have a question for you or anybody that really knows about this type of drives technology. Does the SM951 M.2 Pci-e Gen3 SSD is (NVME) compatible?. The reason I ask is cause I have read on other forums that its not, but if that its true why and how this company its promoting as a model name (NVME) SSD sorry but here its the link for you to check and if you find out that they are, so let me know, cause I will order one my self. thanks for the respond. http://avnetexpress.avnet.com/store/em/E…1&page=1&rank=8

Actually the offered Samsung SM951 M.2 PCIe SSDs do not support NVMe. For details please look >here<.

Yes, Fernan I have seen this info before but my question is, Is this info coming from Samsung that this card its not NVME compatible, if true, why is this company advertising the SM951 as (NVME). Don’t the Bios needs a NVME file or setting in bios to be all compatible and so the PCI-e as well. Also I seen some benchmark on this M.2 card and the numbers are much greater than the XP941. But thanks anyways guy.

It was the company Samsung itself, who announced the NVMe support of the upcoming SM951 some weeks ago, but obviously they didn’t manage it until the release of the SSD to the public.

Yes. Even if the SM951 would support NVMe (it doesn’t actually), you will need a special BIOS module as well to really benefit from the NVMe support.

Hello Fernan good news guy ASUS has release a new BIOS guest what, with NVme Support and USB 3.1 about that, what you think guy. I will give it a try and post the outcomes, if indeed shows NVme in bios, guest what guy, I will buy the SM951. I think ASUS is get ready for the new Windows 10, it should come with native NVme support. Not that Windows 8.1 should have that as well right.

Well update the Bios to 1401 on my X99-Deluxe board, and under advance tools their is always @ the bottom an option for (NVMe) but only says "information of the drive" and since my XP941 its not an NVMe compatable, there is none info of course. I have to wait till I get the SM951 and see if that one is, I will keep it posed.

ASRock has released BIOSes with NVMe support already some weeks ago. So my ASRock Z97 Extreme6 is ready for an M.2 Ultra SSD with NVMe support, but I haven’t yet seen any.

Hey Fernan let me know when you do. I was going to buy the SM951 but I’m going to hold on that one till make for sure is NVMe compatible, keep me posted guy. Thanks.

Hey Ferna, have check if your Z97 MB M.2 option for M.2 cards is a Gen 2 or Gen 3, My question arise cause I read this article in the web.


Hey Fernan I found this article about the XP941 performance states of the drive it self, you might to read on it and if you haven’t notice you can test it and see if this theory is true or not, I think it is cause remember when I post one of my benchmarks the different between yours and mine, I think this is relay to that.


Well yes, I can confirm that, using the XP941 with the C-State disable you can see better results, but while the C-state enable the M.2 it operates on a medium state performance. Any user of this M.2 SSD form factor with a desktop can confirm that by it self, just run Anvil with the C-state features (ON) then after with the package (OFF) then compare difference of the two.

Where and how did you disable the C-State?

Fernan the C-state in BIOS, CPU PWM option, the C0, C1, C2, C3 and so on, turn it off in bios then retest the M.2. A person @ ROG forum has the same performance issue with a SM951 and I replay the person to test this option tweak to see the results. If this hypothesis is true, then there is the performance lost reason.

Note: in conclusion of this, what we are doing by disabling the C-state in bios, is the same tweak that all of us do when you install the the rst drivers in a laptop to disable the power link feature, to get better write performance. But the down draw with us since the XP941 and the SM951 use its own data driver so to get the full performance out of this M.2 form factor has to sacrifices the power features on the CPU and no ones like to run theirs CPU at full speed all the time, even when the CPU is not OC. Also you can test this with the CPU at its defaults clock speed but disabling the C-state and you still see the difference in performance, reads and writes. So their is my @Cents hints.

Hey guys, just to let you know I just installed one of these bad boys today in my new GA-Z97X-Gaming G1 WIFI-BK (F7 BIOS also UBU 1.30.1 modified), here are the speeds -

CrystalDiskMark 5.0.2 x64 (C) 2007-2015 hiyohiyo
Crystal Dew World : http://crystalmark.info/
* MB/s = 1,000,000 bytes/s [SATA/600 = 600,000,000 bytes/s]
* KB = 1000 bytes, KiB = 1024 bytes
Sequential Read (Q= 32,T= 1) : 2205.510 MB/s
Sequential Write (Q= 32,T= 1) : 1589.552 MB/s
Random Read 4KiB (Q= 32,T= 1) : 770.284 MB/s [188057.6 IOPS]
Random Write 4KiB (Q= 32,T= 1) : 374.162 MB/s [ 91348.1 IOPS]
Sequential Read (T= 1) : 1887.185 MB/s
Sequential Write (T= 1) : 1580.039 MB/s
Random Read 4KiB (Q= 1,T= 1) : 52.105 MB/s [ 12720.9 IOPS]
Random Write 4KiB (Q= 1,T= 1) : 195.491 MB/s [ 47727.3 IOPS]
Test : 1024 MiB [E: 0.0% (0.2/476.8 GiB)] (x1) [Interval=5 sec]
Date : 2015/08/14 10:46:10
OS : Windows 10 Professional [10.0 Build 10240] (x64)

It is very fast and it boots fine, I currently have 64GB Boot partition, then 365Gb Game Partition and have kept 47Gb free for over provisioning etc.

Got my older Samsung XP951 setup for rest of my data.

Both using Lycom DT-120's