PCIe expansion card for M.2 NVME SSD vs PCIe SSD card

Discussion in 'SSDs & Data Storage' started by tankman1989, Feb 4, 2019.

  1. tankman1989

    tankman1989 Gawd

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    I remember years ago when there was a decent selection of PCIe SSD's that were much more expensive and much faster than standard SATA SSD's. Now that M.2 NVME is out, those PCIe card's seemed to have disappeared. The problem is that I don't have an m.2 port on my MOBO so I looked into an expansion card and found a number that offer anywhere from 1-3 m.2 NVME ports and some with SATA connections as well.

    Now I've found some PCIe cards that are insanely fast (now called Add-in-card AIC SSD's) with IOP's MUCH higher (5-10x) than m.2 NVME and they are basically the same price per GB.

    I'm also concerned about getting the real speed from the m.2 expansion cards, if it will really support the m.2 nvme specs. I remember old SATA expansion cards (2 or 4 port) that really lacked in performance compared to on-board SATA and these new cards are about the same price as the old SATA expansion cards ($20-45).

    Has anyone had experience with these expansion cards or the newer PCIe SSD's? I'm looking at a Plextor
    https://www.newegg.com/Product/Product.aspx?Item=N82E16820249107 which at $120 for 512GB and the speed it offers, it pretty nice IMO.
     
  2. BlueLineSwinger

    BlueLineSwinger Gawd

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    First, my usual link showing how NVMe SSDs are a waste for general desktop use cases, just get a cheaper and/or larger SATA unit. Also, given that your mainboard doesn't have m.2 I'm guessing it doesn't support NVMe boot anyways, and what's the point if you can't run your OS off the fastest drive?

    The basic, single-card m.2-AIC adapters don't do any kind of protocol conversion or anything like that, nor do they require any drivers (example). They're just simple form-factor adapters. A m.2 NVMe SSD used in one will perform identically to one plugged directly into a mainboard's m.2 slot. Same goes for the ones that support a single m.2 NVMe SSD + a single m.2 SATA SSD and have a SATA connector to the mainboard (i.e., don't have their own on-board SATA controller) (example).

    Where it gets more complicated is the PCIe AIC-m.2 adapters that support two or more NVMe m.2 SSDs (example). Most of these will not work with most desktop-class mainboards, as they are incapable of properly bifurcating the PCIe slot (e.g., 16x) to the individual drives (e.g., four 4x m.2 slots). To use such an adapter would require one of the really expensive models with an on-board PCIe switch to perform the bifurcation, or a workstation/server-class system whose chipset and BIOS have proper built-in bifurcation support.

    Where are you finding NVMe AICs that perform so much better than m.2 units for the same price? Only way I can see pulling that off is picking up used enterprise-grade units, such as the Intel P3x00 series, from eBay.

    That Plextor's given specs look about the same as any other current consumer-level NVMe SSD, m.2 or AIC. Don't know anything about it myself, really. See if you can find some reviews.
     
  3. tankman1989

    tankman1989 Gawd

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    What I mentioned as far as being better or faster was in the read/write IOPS which the Plextor had much higher than most other NVME's at 4k size (which is what the others measure at as well).

    The Plextor had a 340,000/280,000 Read/Write and the others had 10,000 - 90,000 Read and 40,000 - 90,000 Write, some of them did go to about 1/2 the Plextor at 140,000-180,000 Read and 110,000-130,000 Write - I got these numbers from the Newegg compare feature where it listed them for the drives.

    I looked again and this is especially true for the standard SATA drives, they have MUCH lower IOPS than the NVMe, and much of the m.2 were were similar to the standard SATA's.

    I just thought that the IOPS would make the drives perform faster as that seems how it would handle reading/writing smaller chunks of data. IDK if I'm mistaken in that fact, but that is how I've understood it.

    edit - I did just see that some of the drives list an IOPS for a Q1 and Q32 and the speeds greatly differ in those, with the Q1 being lower and the Q32 being higher by about a factor of 16, which seems an interesting fact...
     
  4. BlueLineSwinger

    BlueLineSwinger Gawd

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    Like I said, those specs are roughly equivalent to other current NVMe units: Samsung 970 Evo, WD SN750.

    But, as the numbers linked from Tech Report show, they're largely irrelevant for a desktop system. Six-figure IOPS and multi-gigabyte copy speeds really don't mean much of anything when web browsing or gaming.
     
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  5. daglesj

    daglesj [H]ardness Supreme

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    What the man said!

    Plus if you don't have a M.2 slot then maybe your board doesn't even have PCI-Express 3 capability.
     
  6. dbwillis

    dbwillis [H]ardness Supreme

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    I have the Plextor 1tb model, an older one, it worked great in a few HP machines and my home server, this AM I actually removed the m2 drive and put that directly onto the MB of a new build, works fine