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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  • sandtitz - Wednesday, December 25, 2019 - link

    ASRock Ultra Quad from yesteryear had double the performance. Price without drives: $80 vs $250. Why would any PC owner choose this OWC model?
  • Billy Tallis - Thursday, December 26, 2019 - link

    This OWC card has a PCIe switch, so it doesn't rely on the host motherboard supporting PCIe bifurcation and being able to provide four lanes per SSD. It'll work in any x8 or x16 slot and isn't limited to two M.2 drives when used in an x8 slot.
  • Freeb!rd - Thursday, December 26, 2019 - link

    Yeah, I was wondering the same... bought a Sabrent 1TB Gen4x4 drive; it does a steady 3.9GB Write & 4.3GB Read in a new 3900X/X570 build and it only set me back about $167 after taxes on Amazon (had a $11 coupon which pretty much covered the tax bill). 2TB must be getting scare though, price has jumped up to ~$500 on Amazon and I'm sure it was around $350 when I was shopping for the 1TB early last week. Some X570 boards are bundling in a 4 NVMe slot Gen4x16 add-in card... whoopie!
  • flyingpants265 - Sunday, December 29, 2019 - link

    Remember Gigabyte i-RAM? That was so cool, but I guess we don't even need that anymore.

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