Amfeltec x16 PCIe with 4 SSDs: 5900+ MB/s

Discussion in 'Mac Pro' started by cerberusss, Nov 9, 2015.

  1. h9826790 macrumors G5

    h9826790

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    #201
    My understanding is that PCIe 2.0 x4 SSD is fine, but PCIe 3.0 x4 SSD will be throttled down to PCIe 1.0 x4 speed in slot 2 for unknown reason. The Amfeltec card is not a ordinary x4 card but x16 card, that may be the reason why it works.

    Since you said some of your HyperX Predator works fine, some other throttled down to 1.0 (half speed), I am thinking if some of the SSD are actually PCIe 3.0, but not 2.0.
     
  2. itdk92 macrumors 6502

    itdk92

    Joined:
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    Location:
    Copenhagen, Denmark
    #202
    But only on Slot #2
    Slot 3 or 4 worked perfectly.

    Happened recently also with a Samsung EVO 960 1TB

    750MB/s read and write on Slot 2 and 1550MB/S read and write on slot 3 - 4 o_O
     
  3. h9826790 macrumors G5

    h9826790

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    #203
    Yes, it's a known issue, only happen on x16 slot (I bet it happen in slot 1 as well, but of course no reason to put the SSD into that slot), but not the x4 slots.

    960 Evo is a PCIe 3.0 x4 card, definitely fall into the affected group.
     
  4. itdk92 macrumors 6502

    itdk92

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    #204

    I think something else is happening,
    because my Samsung 960 work perfectly on my Amfeltec in slot 2 (x16)
     
  5. h9826790 macrumors G5

    h9826790

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    #205
    It a known issue with the normal x4 adaptor + PCIe 3.0 x4 SSD combo, the Amfeltec card is NOT affect in any slot.
     
  6. joevt macrumors 6502

    Joined:
    Jun 21, 2012
    #206
    1) Slot 3 and 4 use a different PCIe controller than Slot 1 and 2.
    2) Different PCIe 3.0 devices may have different behavior with different PCIe 2.0 controllers. They may skip PCIe 2.0 speed and drop to PCIe 1.0 speed.
    3) Each NVMe drive is it's own PCIe device.
    4) The amfeltec dual and quad cards use a PCIe switch between the slot and the NVMe drives. So the PCIe device connected to the slot's PCIe controller in that case is the switch. The Gen3 card may drop to Gen1 speed but only for the upstream port of the switch (connected to the PCIe slot) - the NVMe drives are separated from the PCIe slot by the switch and continue to work at Gen3 speed (downstream ports of the switch). The Gen2 card is more compatible, but the NVMe drives drop to Gen2 speed because the switch chip is Gen2. You can confirm this using the lspci command.
    5) The switch chip on the amfeltec Gen3 dual and quad cards has the advantage of being able to convert PCIe 3.0 x4 to PCIe 1.0 x8 or x16 (or PCIe 2.0 x8 or x16 in a compatible slot - of which the Mac Pro's slots are not). A card supporting only one NVMe drive can only support x4.
    The switch chip on the amfeltec Gen2 quad card has the advantage of being able to convert PCIe 2.0 x4 to PCIe 1.0 x8 or x16. A card supporting only one NVMe drive can only support x4.
     
  7. joevt, Oct 12, 2017
    Last edited: Oct 12, 2017

    joevt macrumors 6502

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    #207
    I've received an amfeltec Gen3 quad M.2 card and did some tests. The lspci command (which I downloaded from https://github.com/pciutils/pciutils ) confirms that it starts at 2.5 GT/s x16 in slot 2 of my Mac Pro 2008.

    The following command makes it go to 5 GT/s x16:
    Code:
    # Set Target Link Speed of MacPro3,1 slot 2 root port to 5GT/s
    sudo setpci -s 00:1 CAP_EXP+30.w=2:F
    
    This fix could be put into EFI firmware, or a kernel extension. This fix eliminates any reasons to get the Gen 2 card (except price?) unless there is some other issue?

    I'm waiting for more NVMe drives to test the 5 GT/s x16 performance because there is no difference with only one NVMe drive for the Gen 3 card when it runs on a link that can do 4 GB/s (2.5 GT/s x 16, 5 GT/s x8, 8 GT/s x4).
     
  8. belongV2 macrumors newbie

    belongV2

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    #208
    I wish I had that kinda limitation. LOL
     
  9. interzone826 macrumors newbie

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    Oct 16, 2017
    #209
    There will probably be suggestions below to check the temp of your SM951s, in case of throttling. But this might also help. Check the "recondition" feature: https://diglloydtools.com/disktester.html.
     
  10. AidenShaw, Oct 16, 2017
    Last edited: Oct 16, 2017

    AidenShaw macrumors P6

    AidenShaw

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    #210
    Apparently the writer of that article has never heard of TRIM. The advice in the article is very, very bad.

    It says: "I would need to erase the file system on the drive, so that I could write to its entire capacity".

    This is a horrible thing to do to an SSD - unless TRIM is active. (And if TRIM were active, they'd never see the slow writes that they're trying to fix.)

    It's just bad advice.

    Read https://en.wikipedia.org/wiki/Write_amplification to understand why it is so bad.
     
  11. belongV2, Oct 17, 2017
    Last edited: Oct 24, 2017

    belongV2 macrumors newbie

    belongV2

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    #211
    Remove 2 dimms might be able to solve your current problem, 48gb instead of 64gb. And for benchmark try Xbench instead of AJA.
     
  12. joevt macrumors 6502

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    Jun 21, 2012
    #212
    I've received 4 Samsung 960 Pro 1TB SSDs and did some tests to confirm that 5 GT/s x16 works in the 2008 Mac Pro.

    To change the link speed of a card:
    1) Find the location of the card using "sudo lspci -nnvt". The following is the results of the amfeltec card in slot 1 of the 2008 Mac Pro.
    Code:
    -[0000:00]-+-00.0  Intel Corporation 5400 Chipset Memory Controller Hub [8086:4003]
               +-01.0-[01]--+-00.0  NVIDIA Corporation GK104 [GeForce GTX 680] [10de:1180]
               |            \-00.1  NVIDIA Corporation GK104 HDMI Audio Controller [10de:0e0a]
               +-05.0-[02-07]----00.0-[03-07]--+-08.0-[04]----00.0  Samsung Electronics Co Ltd NVMe SSD Controller SM961/PM961 [144d:a804]
               |                               +-09.0-[05]----00.0  Samsung Electronics Co Ltd NVMe SSD Controller SM961/PM961 [144d:a804]
               |                               +-0a.0-[06]----00.0  Samsung Electronics Co Ltd NVMe SSD Controller SM961/PM961 [144d:a804]
               |                               \-0b.0-[07]----00.0  Samsung Electronics Co Ltd NVMe SSD Controller SM961/PM961 [144d:a804]
    
    2) The root port containing the amfeltec gen 3 card is at PCIe bus 00, device 05, function 0, or "00:5"
    3) Use the following commands to change the link speed (set the speed and root port variables). In the Mac Pro, the possible values are 1 (2.5 GT/s 8b/10b) or 2 (5 GT/s 8b/10b). A Hackintosh may have PCIe 3.0 slots supporting speed 3 (8.0 GT/s 128b/130b).
    Code:
    # Set Target Link Speed to 2.5GT/s of MacPro3,1 slot 1 root port
    speed=2
    rootport=00:5
    linkstatus=$(sudo setpci -s $rootport CAP_EXP+12.w); echo '# Before: PCIe' $(( 0x$linkstatus & 15)).0 x$(( 0x$linkstatus >> 4 & 31))
    sudo setpci -s $rootport CAP_EXP+30.w=$speed:F # Set Link Speed
    sudo setpci -s $rootport CAP_EXP+10.w=20:20 # Start Retrain
    linkstatus=$(sudo setpci -s $rootport CAP_EXP+12.w); echo '#  After: PCIe' $(( 0x$linkstatus & 15)).0 x$(( 0x$linkstatus >> 4 & 31))
    
    I've tested various link speeds of the gen 3 amfeltec card in both a 2008 Mac Pro and a Hackintosh (GA-Z170X Gaming 7). The 2008 Mac Pro seems to be able to get only slightly above 4000 MB/s using 5GT/s x16. This is much lower than the 2010 Mac Pro is capable of with the gen 2 amfeltec card, but it is still greater than what 2.5 GT/s x16 allows which proves that 5 GT/s x16 is working. It may be that the 2008 Mac Pro's CPU and RAM don't allow this benchmark to saturate the PCIe slot's bandwidth which means that a gen 2 amfeltec card would have the same result in the 2008 Mac Pro.

    In the Hackintosh, I tested both x8 and x16 slots using AJA System Test Lite 12.4.3. The following are for the average Read speeds for 16 GB file size:

    x8 slot:
    1. At speed 1, the x8 slot is saturated by one SSD (1610 MB/s).
    2. Full performance from one SSD requires speed 2 (2880 MB/s).
    3. At speed 2, the x8 slot is saturated by two SSDs (3099 MB/s).
    4. Full performance from two SSDs requires speed 3 (4998 MB/s).
    5. At speed 3, the x8 slot is saturated by three SSDs (5376 MB/s).
    6. In an x8 slot, full performance from three SSDs is not achievable.
    7. In an x8 slot, full performance from four SSDs is not achievable.

    x16 slot:
    1. At speed 1, the x16 slot cannot be saturated by one SSD.
    2. Full performance from one SSD requires speed 1 (2864 MB/s).
    3. At speed 1, the x16 slot is saturated by two SSDs (3047 MB/s).
    4. Full performance from two SSDs requires speed 2 (4924 MB/s).
    5. At speed 2, the x16 slot is saturated by three SSDs (5304 MB/s).
    6. Full performance from three SSDs require speed 3 (6359 MB/s).
    7. Full performance from four SSDs requires speed 3 (7467 MB/s).
    You can see that each x16 result is similar to the x8 result at double the speed.

    The speed 2 x16 result is similar to the 2010 Mac Pro barefeats.com result for the gen 2 amfeltec card meaning that both cards and both computers are able to saturate the PCIe 2.0 x16 slot but the gen 3 card can do that with just 3 SSDs.
     
  13. interzone826 macrumors newbie

    Joined:
    Oct 16, 2017
    #213
    Is your command useful only for a 2008 Mac Pro? Would it be needed if using the same Amfeltec card on a mid 2012 Mac Pro?
     
  14. joevt macrumors 6502

    Joined:
    Jun 21, 2012
    #214
    If the 2012 Mac Pro boots with the gen 3 amfeltec card set to gen 1 speed then you need to use the command to get gen 2 speed. I suppose a kernel extension would be preferable, or a EFI patch which can affect all OSs that you choose to run on the Mac (macOS, Linux, Windows).

    The commands should work on any computer. I also used it on a Hackintosh with PCIe 3.0 slots to test PCIe 2.0 and PCIe 1.0 speeds.

    I redid the tests using SoftRaid 5.6.3 (64K stripe size – optimized for workstation) and AJA System Test Lite 12.4.3 3840x2160 4K RED HD, 16 GB file size, 16bit RGB. My previous results used Disk Utility.

    Results:

    MacPro3,1 x16 slot 2:
    1. At speed 1, the x16 slot cannot be saturated by one SSD.
    2. Full performance from one SSD requires speed 1 (2942 MB/s).
    3. At speed 1, the x16 slot is saturated by two SSDs (3045 MB/s).
    4. Full performance from two SSDs requires speed 2 (5086 MB/s).
    5. At speed 2, the x16 slot is saturated by three SSDs (5226 MB/s).
    6. Full performance from three SSDs is not achievable.
    7. Full performance from four SSDs is not achievable (performance drops to 4985 MB/s).

    Hackintosh x8 slot:
    1. At speed 1, the x8 slot is saturated by one SSD (1658 MB/s).
    2. Full performance from one SSD requires speed 2 (3140 MB/s) or speed 3 (3194 MB/s).
    3. At speed 2, the x8 slot is saturated by one (3140 MB/s) or two SSDs (3270 MB/s).
    4. Full performance from two SSDs requires speed 3 (6032 MB/s).
    5. At speed 3, the x8 slot is saturated by three SSDs (6199 MB/s).
    6. In an x8 slot, full performance from three SSDs is not achievable.
    7. In an x8 slot, full performance from four SSDs is not achievable.

    Hackintosh x16 slot:
    1. At speed 1, the x16 slot cannot be saturated by one SSD.
    2. Full performance from one SSD requires speed 1 (3171 MB/s) or speed 2 (3198 MB/s).
    3. At speed 1, the x16 slot is saturated by one (3171 MB/s) or two SSDs (3277 MB/s).
    4. Full performance from two SSDs requires speed 2 (6091 MB/s) or speed 3 (6165 MB/s).
    5. At speed 2, the x16 slot is saturated by three SSDs (6315 MB/s).
    6. Full performance from three SSDs requires speed 3 (8733 MB/s).
    7. Full performance from four SSDs requires speed 3 (11141 MB/s).

    Summary:

    The MacPro3,1 slot 2 results are much more reasonable now. It’s probably still not as good as the 2010 Mac Pro but much closer than before.

    The Hackintosh results are much improved. SoftRaid’s RAID 0 performance scaling is much more linear. SoftRaid’s performance for a single SSD is so good that you can get slightly more performance by doubling the link bandwidth of the upstream port. Poor performance from the gen 3 x4 NVMe SSD would see no benefit from a better upstream link (the links are like pipes, and small items going through the pipe are not hindered by misaligned pipes). When the performance of the SSD nears the limit of the gen 3 x4 M.2 slot, then an upstream link of the same bandwidth (gen 1 x16 or gen 2 x8 or gen 3 x4 - which is not tested here) would have a slight negative impact because it has a similar limit (like two pipes of the same size but not perfectly aligned). This is why you can get slightly more performance (between 30 and 100 MB/s) from one fast SSD (gen 3 x4) when the upstream port has more bandwidth (gen 2 x16 or gen 3 x8) (the little pipe fits in the big pipe even if it’s not centered).
     
  15. lneuman macrumors newbie

    lneuman

    Joined:
    Oct 30, 2017
    #215
    Has anyone used the Amfeltec carrier board with a Thunderbolt PCIe expansion chassis? Barefeats has an article where they used a TB3 patch, but I was wondering if this is still necessary for a Sonnet Echo Express SE III TB3 chassis.

    http://barefeats.com/tricktb3.html

    I would love to have these speeds on an iMac or MBP without any hacks.

     
  16. joevt macrumors 6502

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    #216
    Sonnet states the Sonnet Echo Express SE III is Mac compatible, so it doesn't need the Thunderbolt 3 enabler patch.
     
  17. iamtheonlyone4ever Suspended

    iamtheonlyone4ever

    Joined:
    May 27, 2016
    #217
    gen 2 is for recommended for Mac because the Mac pros are pci-e 2.0 and you will get better performance using Squid PCI Express Gen 2 Carrier Board on a Mac pro but if you have a hackintosh that use pci-e 3.0 then you get the maximum speed using Squid PCI Express Gen 3 Carrier Board

    is not that Squid PCI Express Gen 2 is faster than Squid PCI Express Gen 3
    is just that version 2 runs better on a Mac Pro
    version 3 is definitely faster but it won't work as good as version 2 on a mac pro because the pci-e 2.0 bus speed

    but on a hackintosh a version 3 will smoke and blow a version 2 out of the water
    as long as that hackintosh has a 16X pci-e 3.0 slot

    this is the new card but it is for Mac Pro 2013
    http://amfeltec.com/products/mac-pro-late-2013-carrier-board-for-m-2-pcie-ssd-modules/
     
  18. RyanXM, Nov 30, 2017
    Last edited: Nov 30, 2017

    RyanXM macrumors 6502

    RyanXM

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    DFW, TX
    #218
  19. iamtheonlyone4ever, Nov 30, 2017
    Last edited: Nov 30, 2017

    iamtheonlyone4ever Suspended

    iamtheonlyone4ever

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    May 27, 2016
    #219
    good question , I know you didn't asked me but I found out about this, some cards do requiere a compatible motherboard that supports that option "bifurcation" 4x4x4x4x = 16X ,but if I'm not mistaken and I understood things correctly there are some card that doesn't need or requiere "bifurcation" because they have some special chip on the m.2 adapter board that takes care of that and it will see the card as a single 16x card, I can't confirmed this because I just read about it in some page but I will order my squid gen 3 tomorrow , then I will know for sure, I really like that card but man that green pub color is killing me but that card is the best option, is bootable on Mac OS , I have a hackintosh so gen 3 is the option for me but now the problem is High Sierra, I will only be able to raid using HFS+ that is if I want to use the card as bootable device, if I'm going to use the card as storage only then I can make the raid on APFS.
    if any of those 2 Macs don't have support for bifurcation then you need to Get a card that doesn't requiere that feature or option.
    --- Post Merged, Nov 30, 2017 ---
    what I really like is the pcb color that is brown , while the squid gen 3 is green , I really will like a brown card but the ones that are brown do no work for Mac or hackintosh, they are windows only and some of them are not even bootable, they are storage only like the new good looking high point card, that one looks beautiful but no Mac support and they are storage only. I'm so upset haha
     
  20. joevt macrumors 6502

    Joined:
    Jun 21, 2012
    #220
    I guess you didn't read my later post #214 where I show that the Squid Gen 3 is faster than the Gen 2 for one SSD even when it runs at Gen 1 speed.

    I also showed how to get the Gen 3 card to work at Gen 2 speed, which gives better performance for two SSDs in raid 0 than the Gen 2 card. The Gen 3 card can saturate the Gen 2 slot with three SSDs in Raid 0, but the Gen 2 card requires four SSDs in Raid 0 to do that.

    Amfeltec support said the following:
    "We are planning to include in the next Carrier board Gen 3 revision hardware option for downgrade connection speed to Gen 2. The new rev we are planning to release in end of Q4 / beginning Q1."


    Macs don't support bifurcation.
    The amfeltec cards use a PCI Express Switch chip. The lspci command shows that the Gen 3 card uses the following:
    Code:
    PCI bridge [0604] (class code): PLX Technology, Inc. PEX 8732 32-lane, 8-Port PCI Express Gen 3 (8.0 GT/s) Switch [10b5:8732] ([vendor id:device id]) (rev ca)
    
    A switch chip has an upstream port and a one or more downstream ports. The Squid Gen 3 uses 5 ports, and all 32 lanes of the PEX 8732. The upstream port (connected to the PCIe slot) is x16. The four downstream ports (connected to the NVMe devices) are each x4. The upstream port can run at Gen 1, Gen 2, or Gen 3 speed (The classic Mac Pro PCIe slots support Gen 1 and Gen 2 speeds). The downstream ports match the speed of the connected NVMe device (usually Gen 3).
     
  21. RyanXM macrumors 6502

    RyanXM

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    DFW, TX
    #221
    What version of macOS are you installing the PCIUTILS onto? High Sierra doesn't seem to be supported.
     
  22. iamtheonlyone4ever, Nov 30, 2017
    Last edited: Nov 30, 2017

    iamtheonlyone4ever Suspended

    iamtheonlyone4ever

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    May 27, 2016
    #222
    yes most likely I missed that part, I don't know if the squid card supports windows on a PC because the lack of documentation in Amfeltec web site, but they do work on a hackintosh PC to install Mac OS, at this point I don't know if windows is supported. another important part that is missing is how high can the card really go, let's just say with 4 samsung pro or evo, no info is available either, the problem that I have is with the 4th m.2 disk , I have no where to install it because I have a Nvidia 1080 card but with just 3 regular 4x pci-e cards I get over 8,000 in read speed and over 4,000 in write , don't remember the actual number right now, that's why I need a 16x card but I'm not going to pay 580 including shipping and PayPal expenses if the card can only go up t 8000 or 9000, the high point card is certified to reach at least up to 12,000 or even a little bit more depending on what drives are installed, keep in mind that you need a powerful CPU to be able to push the card and the M.2 drive to archive the maximum speed. the only problem with the high point card is that it doesn't support Mac OS, if anybody has any info about if the squid card can go over 10,000 please , I will appreciate, thank you
    --- Post Merged, Nov 30, 2017 ---
    about what you told me, there are 2 articles in bare feet
    this is one is for gen 2
    http://barefeats.com/hard210.html
    and this one is for gen 3
    http://barefeats.com/hard220.html
    there you will be able to see and understand the differences between the 2 with different test
     
  23. joevt macrumors 6502

    Joined:
    Jun 21, 2012
    #223
    I'm using High Sierra. I use pciutils from https://github.com/pciutils/pciutils
    Download the zip then use Terminal.app to execute these commands:
    Code:
    cd ~/Downloads/pciutils-master
    sudo make install
    
    Then append /usr/local/sbin to the file /etc/paths
    Then in a new Terminal.app window, execute:
    Code:
    sudo update-pciids
    sudo nvram boot-args="debug=0x144"
    
    Restart the computer. Now you can run some pciutils commands like this:
    Code:
    sudo lspci -nnvt
    
    I've attached a script that does the same thing as "lspci -nnvt" except it also lists the PCIe switches, and the link width and link speed capability (max values) and status (current values). It includes example output from a Z170X Gaming 7 with a OWC Thunderbolt 2 dock connected to a OWC Thunderbolt 3 dock.
    Make sure the script has execute privilege.
    Code:
    chmod 744 pcitree.sh
    
    Then execute it like this:
    Code:
    sudo pcitree.sh
    
    --- Post Merged, Dec 1, 2017 ---
    Windows has drivers for PCI switches, SATA drives, and NVMe drives. The amfeltec card does nothing special. I'm not sure there's a way that it couldn't be supported in Windows...

    You need to reread my post a third time. It includes a test where I got over 11GB/s in macOS using an x16 slot in a Hackintosh. The Hackintosh I used only has one x16 slot. You need to check with your motherboard documentation for the options available to you. The benchmark and OS I used may produce different results than the benchmark and OS used for that High Point card. The point is that you can achieve greater than the maximum theoretical performance of a PCIe 3.0 x8 slot (or a PCIe 2.0 x16) slot when you use a PCIe 3.0 x16 slot.

    I've emailed rob-ART to update/correct those articles with the information from my tests. To reiterate, the problem with the gen 3 card in the Mac Pro is that the upstream port starts up at gen 1 speed instead of gen 2 speed. The down stream ports start up correctly at gen 3 speed, making the gen 3 card faster than the gen 2 card anyway for individual M.2 devices. You can set the gen 3 card's upstream port to gen 2 speed after startup. You could create some code to do that in EFI, so it works with any OS, before the OS starts.
     

    Attached Files:

  24. iamtheonlyone4ever, Dec 1, 2017
    Last edited: Dec 1, 2017

    iamtheonlyone4ever Suspended

    iamtheonlyone4ever

    Joined:
    May 27, 2016
    #224
    I only read the post where you replied to me, but now I will read that post that you mentioned, thanks
    about the barefeet article when they did the test with the NVME m.2
    at that time the only driver available was the one from macvidcards
    and it was a buggy driver then a better solution came out
    finally apple implemented native support for 3rd party nvme drives in HS
    I'm sure if they make a new test today they will have better results than in the past
    when they used the first buggy driver to test the nvme m.2 drives

    finally just read your post very interesting post , this part does it for me
    Hackintosh x16 slot:
    7. Full performance from four SSDs requires speed 3 (11141 MB/s).

    that was exactly was I was looking for
    thank you very much

    just in case , what drives you have, I'm sure with the speed result they has to be samsung 960
    most likely, I got 4 evos but my goal is at least 10,000 I'll be more than happy with that.
    but I'm sure than I can reach 11,000 with 4 evos because I was hitting around 8400 or 8600 with just 3
    once again thanks and sorry for missing your post before
    --- Post Merged, Dec 1, 2017 ---
    I ordered the card

    [​IMG]
     
  25. joevt macrumors 6502

    Joined:
    Jun 21, 2012
    #225
    The first two Barefeats articles used 512 MB SM951 AHCI M.2 drives.

    The first article dealing with the gen 2 card concluded that NVMe would not be faster than AHCI because the Gen 2 card is limited to PCIe 2.0 x4 1500 MB/s. It also concluded that you wouldn't be able to boot from NVMe. That might not be entirely correct: it may be possible to copy an NVMe EFI driver to make that possible (as some have done on Hackintosh).

    The second article dealing with the gen 3 card concluded that you would get best performance in a classic Mac Pro using the gen 2 card. That is not entirely correct because you can get full/better performance in the classic Mac Pro from individual M.2 devices (no raid) using the gen 3 card. It also stated that the speed advantage of NVMe flash is nullified on the Mac Pro tower. That is referring to the gen 2 card though. The tests in the article show that even an AHCI drive can exceed 2GB/s in the gen 3 card. The article states "the PCIe 3.0 Carrier Board's controller gets 'lost in translation" which is a terribly uninformative description of the problem. There is a solution to that problem but it is not mentioned.

    There is a third article http://barefeats.com/hard225.html using 512 MB 960 Pro NVMe drives in High Sierra. It seems to downplay the speed advantage of the gen 3 card for individual M.2 devices. The tests show the speed advantage but the conclusion is not very enthusiastic about it - for people that don't plan to raid.

    For my tests, I used four 1TB 960 Pro NVMe drivers as stated in my first tests in #212 using Apple Raid (Disk Utility.app). The updated tests in #214 used SoftRaid which gave much better results.


    I was quoted $465.00 USD + $59.66 USD taxes for the card SKU-086-34 (I'm in Canada) on Oct 2. The card is expensive because of the PEX 8732 switch chip (about $170) I'm not sure what the other $300 is for. Cards that require PCIe bifurcation don't use a switch chip (they use the motherboard's switching capabilities for the slot) and are therefore much less expensive ($200?).
     

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