XPS 13 9360, Samsung Pro 970, RAID, boost speed

If you are running the system with the SATA controller set to RAID, you are running the drive in SATA mode using the SATA controller.    If you want to check, open the Device Manager and select the drive.  Then go to the View options and select "Devices by connection".  It will be hanging on a SATA connector or a NVMe controller depending on the Bios SATA setting.

To get better performance, you need to run the drive in AHCI mode so the NVMe controller will be used.  Along with that you need to install the Samsung NVMe driver.

My Inspiron 15 7567 is showing 2662/1765 for a 960 EVO.  An  XPS 13 9365 only shows the 1800 mentioned with the 960 Pro. I was thinking they had taken some PCIe lanes for the Thunderbolt but JP may be correct. 

If you wanted to change from RAID to AHCI, there is a specific procedure you need to use so the system does not go into the Repair mode.

On a Desktop system with a dedicated M.2 PCIe slot, I am getting around 3600.

Changing from RAID to AHCI or tinkering with the Samsung NVMe driver will not change performance in any meaningful way on this system because of the bottleneck I already described. I tested a 960 Evo in the same model system using RAID, AHCI with the standard Microsoft driver, and AHCI with the Samsung NVMe driver, and I consistently got 1.8xx GB/s. The variations from different benchmark iterations were minor and not consistent. This is a hardware/firmware-level bottleneck that will not go away by changing settings or drivers. And contrary to what Saltgrass says, it is not possible to run an NVMe SSD over SATA. The fastest SATA standard is SATA 6 Gbps (gigaBITS), which is 750 MB/s. Obviously you’re exceeding that by a wide margin, which should be proof enough on its own that Saltgrass is wrong. Then there’s the fact that systems with M.2 slots that only support SATA cannot use NVMe SSDs even when the system is set to RAID mode. If Saltgrass were right that that setting caused NVMe SSDs to use SATA, then those systems should work with NVMe SSDs — but they can’t, because he’s not, and yet he continues to insist that NVMe traffic can be passed over SATA.

When you run in RAID mode, the Intel RST controller — which is itself on the PCIe bus as any physical RAID controller in another system would be — is placed in front of both the SATA and NVMe interfaces. But SATA SSDs continue to interface with that controller over SATA, and NVMe interfaces continue to interface with the controller on NVMe, not SATA. The more recent releases of the RST driver even identify the controller as “Intel Chipset SATA/PCIe RST Premium Controller”, and when you have a system in RAID mode and view Device Manager sorted by connection, the SSD shows as attached to that.

@Saltgrass, take a look at the first post in this thread, right from an official Dell source: https://www.dell.com/community/Laptops-General/Dell-M-2-FAQ-regarding-AHCI-vs-RAID-ON-Storage-Drivers-M-2-Lanes/td-p/5072571

The explanation of RAID mode says absolutely nothing about running NVMe over SATA (only about loading an AHCI interface, which is not the same thing), nor does the stack diagram. Yes, the Device Manager “by connection” screenshots show the NVMe SSD as connected to a “SATA RAID” controller in RAID mode, but that is purely due to an old display name for that driver, which as I said has since been updated. Is that really all you’ve been basing your claims on? If it weren’t for driver signature enforcement, you could edit the INF for that driver before installing it to make it say, “Intel 1990s-era IDE/Parallel ATA Controller”. That wouldn’t mean it actually uses IDE/PATA.

All the Precision 5510 runs is SATA?? Official datasheet specifically mentioning PCIe storage support linked below. That support is even highlighted as a feature in the “Powerful performance” description section, not just in the specs —  as if the existence and functioning of NVMe SSDs in that system, even in AHCI mode, and the ability to order them from the factory wasn’t enough. No, it’s not hard to understand how it uses PCIe storage. What’s hard to understand is why you preferred a “PCIe over SATA” theory over the much simpler explanation that you might simply have been wrong about the system’s capabilities: http://i.dell.com/sites/doccontent/shared-content/data-sheets/en/Documents/Dell-Precision-15-5000-Series-5510-Spec-Sheet.pdf

You never said anything about passing NVMe over SATA?? The OP has an NVMe SSD and earlier in this thread you said, “If you are running the system with the SATA controller set to RAID, you are running the drive in SATA mode using the SATA controller.” How else should that be interpreted?

Ubuntu doesn’t see NVMe drives unless the system is in AHCI mode because its kernel has native NVMe support but not a new enough Intel RST driver to cover the newer controllers.

A PCIe to SATA bridge allows SATA drives to be connected to the bridge so that their traffic can be sent over PCIe. Any SATA RAID controller works this way. It would not allow a PCIe SSD to pass traffic over SATA, just as a SATA to USB bridge allows running a SATA drive over USB, but not a random USB device over SATA.

You’re right that none of this helps the OP, but what doesn’t help any OP around here is when people spread inaccurate information, especially when they phrase their falsehoods as fact rather than hedging with something like, “I believe...” You are absolutely wrong that PCIe SSDs ever run over a SATA interface in any firmware configuration, and continuing to stand by that claim is what’s not helping anyone. When a system is in RAID mode, both PCIe SSDs and SATA drives run over an RST controller. That RST controller happens to support SATA, and in systems that have NVMe support, that same controller ALSO supports NVMe. Each type of storage device interfaces with the RST controller over its native interface, and the RST controller then interfaces with the rest of the system over PCIe.

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@jphughan wrote:

 And contrary to what Saltgrass says, it is not possible to run an NVMe SSD over SATA. The fastest SATA standard is SATA 6 Gbps (gigaBITS), which is 750 MB/s. Obviously you’re exceeding that by a wide margin, which should be proof enough on its own that Saltgrass is wrong. Then there’s the fact that systems with M.2 slots that only support SATA cannot use NVMe SSDs even when the system is set to RAID mode. If Saltgrass were right that that setting caused NVMe SSDs to use SATA, then those systems should work with NVMe SSDs — but they can’t, because he’s not, and yet he continues to insist that NVMe traffic can be passed over SATA.

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You were working with someone on a Precision 5510 in another thread.  It does not show a PCIe Storage Interface.  Since all it runs is SATA, sort of hard to understand how the PCIe NVMe drive was being controlled.

I never said anything about NVMe traffic being passed over SATA.  I did say I had seen where the IRST had been modified to take advantage of the NVMe controller. 

Ubuntu will not see a PCIe drive unless the SATA controller is set to AHCI.

There is such a thing as a PCIe to SATA bridge.

Again, this does not help the OP.  My suggestion will always be, if you have a NVMe drive which has it own NVMe driver, I would go that way.  Even if the performance numbers don't justify a change, running a drive in its native configuration is better than the alternative.

Id tried AHCI mode for the first installed but unfortunately same performance on RAID mode.

It seems the PCIe performance is limited on the XPS 13 systems, which I acknowledged regarding my 9365.  Just make sure you are not using the Microsoft NVMe driver.

@jphughan the following is from the Precision 5510 manual.

Table 19. Storage
Feature Specification
Storage:

Storage Interface SATA 3 Gbps SATA 6 Gbps

Drives configurations:
Hard Drives (optional) one internal 2.5 inch SATA HDD (supports Intel Smart Response Technology)

Solid State Drives (optional) one Solid State Drive (SSD), with Intel Cache support
Size: 512 GB and 1 TB
41

The 9350 or 9550 system you mentioned in that same thread does show a PCIe interface. 

The OP ls free to take whatever configuration he wants.

@Saltgrass, that's hardly the first time Dell's specifications have been incomplete/inaccurate.  Even if it were possible to run PCIe SSDs over SATA -- which it emphatically is not -- if the system only had SATA 3 Gbps and SATA 6 Gbps interfaces and ran installed PCIe SSDs over one of those, then those SSDs would max out at 750 MB/s, which is clearly not what's happening with these systems in the real world, regardless of SATA Operation setting.  Just like the XPS 13 9350 and 9360, the Precision 5510 supports PCIe SSDs -- in fact the 5510 has even better support since it doesn't have this inherent bandwidth limitation -- and using Dell's factory default RAID setting does not throttle PCIe SSDs to SATA levels because that setting doesn't cause PCIe to run over SATA.  If you want to keep grasping at straws like incomplete specs, claim in one post that RAID mode causes PCIe SSDs run over a SATA controller and then in the very next post claim that you never said anything about sending NVMe traffic over SATA, and generally ignore the reality of how systems are operating in the real world, all just to avoid acknowledging that you were wrong about something, then you're of course free to do that.  I just would've expected/hoped that someone who's willing to be here to help others would prioritize providing consistently accurate information a bit more highly.

Y Rand,

What did you do to install this on the 9360. My current NVMe THNSN5512GPUK NV is almost full. I bought a 970 Pro 1 TB. I brought it to some computer place that was well reviewed to do it as I didn't have the time, tools, or hardware. Paying someone 50 bucks to do it sounded like a better alternative. However they couldn't do it. They told me they were trying to ghost my data to and external drive and tried to bring it back and it would always fail.  

What I wanted done was to clone the drive I have in the comp right now install the new SSD and clone it back.

How did you accomplish this?

Thanks,

I bought an external m.2 enclosure and some tools. Then used macrium. It was one of the easier things I have done. Took about an hour for the whole thing. 

I have the same problem. I upgrated the SSD of my Dell XPS 13 9360R Notebook with a Samsung 970 Pro 512 GB and see the same effects. Has anybody feedback from Dell, if the bottleneck is caused by hardware or firmware? If it is by firmware, Dell should provide a solution, because obviously many customers are affected. I will contact the Dell Technical Support in the next days.

SEL7, what m.2 enclosure did you use. I have yet to fine one that works. Thanks!