Just in time for the launch of Apple's newly redesigned Mac Pro tower, OWC has introduced the ‘fastest SSD [they've] ever built’, the Accelsior 4M2. The high-end solid state drive combines multiple M.2 drives to offer up to 8 TB of storage, with aggregate read/write well over 6000 MB/s.

The OWC Accelsior 4M2 SSD is essentially a PCIe x8 backplane based on the ASMedia ASM2824 PCIe 3.0 switch, which in turn is being used to drive a quartet of PCIe 3.0 x4 M.2 slots. The Accelsior then fills out these slots with four of OWC's Aura P12 M.2-2280 drives (Phison’s PS5012-E12 controller with SLC caching support, DRAM, & Toshiba’s 3D TLC NAND memory). To ensure consistent performance as well as to ensure reliability, the SSD is also equipped with a large heat spreader, as four Aura drives can produce a significant amount of heat.

When it comes to capacity, the Accelsior 4M2 storage solution will be available in 1 TB, 2 TB, 4 TB, and 8 TB raw capacities. OWC in turn rates the SSD for sequential read speeds up to 6318 MB/s, as well as sequential write speeds up to 6775 MB/s.

As is often the case for high-end OWC drives, the Accelsior 4M2 is meant to be used with OWC’s SoftRAID software, which supports various RAID modes (RAID 0, RAID 1, JBOD, etc.). Otherwise the drive can also be used in PCs – despite the Mac-focus, it's presented as a generic PCIe card – but PC users will need to supply their own RAID software.

The OWC Accelsior 4M2 SSDs
  1 TB
2 TB
4 TB
8 TB
Formatted Capacity 931 GiB 1863 GiB 3725 GiB 7451 GiB
Drives 4 × OWC Aura P12 M.2-2280 drives
Phison’s PS5012-E12 controller,
SLC caching support,
DRAM cache,
Toshiba’s 3D TLC NAND memory
(7% overprovisioning)
PCIe Switch ASMedia ASM2824
Internal RAID SoftRAID
Peak Read Speed 6318 MB/s
Peak Write Speed 6775 MB/s
Interface PCIe 3.0 x8
Power Bus powered
Form-Factor Full Height Half Length PCIe
Compatibility macOS 10.13 or later
Windows 10 or later
Warranty 5-year warranty
Price (MSRP) $479.99 $629.99 $949.99 $1,599.99

OWC will start shipments of the Accelsior 4M2 SSDs on the week of December 30th. The barebones card is priced at $249.99, the 1 TB version costs $479.99, whereas the top-of-the-range 8 TB model carries a $1,599.99 MSRP.

Related Reading:

Source: OWC

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  • timecop1818 - Tuesday, December 24, 2019 - link

    Lulz, 8TB model is half price of what Apple wants for 8TB upgrade on the trashPro.
  • Santoval - Tuesday, December 24, 2019 - link

    Very underwhelming. Its max sequential read speed is ~500 MB/s slower than just *two* Aura P12 SSDs, while its max sequential write speed is just ~775 MB/s faster than two Aura P12 SSDs (all set in RAID 0 mode apparently). No word about read/write IOPS either, which suggests they are abysmal, i.e. probably worse than those of the individual Aura P12 SSDs.

    Neither the seq. read speed nor the seq. write speed is bottlenecked from the PCIe 3.0 x8 link (the read is certainly not bottlenecked at all), so where is the bottleneck? In the ASM2824 switch? I have no idea, can a PCIe switch become a bottleneck? Maybe because they weirdly had it kill half the available PCIe lanes (16 incoming lanes from the SSDs, 8 outgoing lanes to the PCIe slot)? Or is OWC's software RAID implementation the bottleneck? Or is MacOS itself the bottleneck? I think I will lose sleep in the coming days contemplating this question :)
  • s.yu - Tuesday, December 24, 2019 - link

    Ah, I was wondering that.
  • The_Assimilator - Tuesday, December 24, 2019 - link

    Hey look it's another piece of overpriced junk from OWC. Must be nice having a captive market that's also stupid and rich.
  • Korguz - Tuesday, December 24, 2019 - link

    then just dont buy it... pronlem solved
  • Korguz - Tuesday, December 24, 2019 - link

    problem solved....
  • Spunjji - Friday, December 27, 2019 - link

  • Korguz - Saturday, December 28, 2019 - link

  • JKJK - Tuesday, December 24, 2019 - link

    This is so stupid. I raided P3700 nvme ssds 5 years ago .... and now, when apple has gotten some decent storage, the speeds are "INSANE".
    You can get over half this speed with ONE PCI-e 4.0 drive today.
    Fucking apple retards.
    People are SO stupid.
  • Tomatotech - Tuesday, December 24, 2019 - link

    This isn’t from Apple.

    That said, some of Apple’s gear has legs on. I recently retrofitted a 2013 MacBook Air, Apple’s cheapest laptop, with an Adata m.2 nvme, and got 1300 mb/s rw. Owner is very happy with it. I don’t know many other 7-year old laptops still in regular use for work.

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