OWC has released their first PCIe SSD, the Mercury Accelsior. OWC has used SandForce controllers throughout its history in the SSD world and the Accelsior is no exception. It is equipped with two SandForce SF-228X controllers, which are the same controllers that can be found inside OWC's other SATA 6Gb/s SSDs. 

The actual design is pretty interesting. OWC has opted to build the SSD out of two blades, each with their own controller and NAND running. The blades run in RAID 0 by default but they can also be configured in RAID 1 mode. Oftentimes everything is intergrated on one PCB but OWC's approach is different, and there is actually a big advantage todoing things this way. Using blades allows the capacity to be upgraded without buying a totally new card. OWC does not sell the blades separately yet, but manufacturing new blades should be somwhat cheaper than manufacturing the whole PCB, so down the road this could result in a lower total upgrade price.

OWC Mercury Accelsior Specifications
Capacity 120GB 240GB 480GB 960GB
Controller Dual SandForce SF-2281 Dual SandForce SF-2282
NAND 24nm Toshiba Toggle-Mode MLC NAND
Interface PCI Express 2.0 x2
Form Factor Low Profile PCI Express
Sequential Read 758MB/s 762MB/s 780MB/s 756MB/s
Sequential Write 743MB/s 763MB/s 763MB/s 673MB/s
4K Random Read Up to 100K IOPS
4K Random Write Up to 100K IOPS
Price $360 $530 $930 $2096
Warranty 3 years

OWC's Mercury Accelsior is actually a very competitive drive. A quick look at NewEgg shows that OCZ's RevoDrive 3 is not significantly cheaper--in fact, it's more expensive at 480GB and above. OCZ does claim better performance but it's good to keep in mind these figures meant for advertising.

OWC is primarily an Apple focused company and here is the big deal: Mercury Accelsior supports booting under OS X. There are plenty of PCIe SSDs out there but OWC's is the first one that supports booting into OS X. No drivers are needed in OS X or Windows either--the drive is plug and play. Booting into Windows has not been a problem but it's understandable that a Mac user has little need for a PCIe SSD that only boots into Windows. Unfortunately Mac Pro is the only Mac that has empty PCIe slots and Apple has not shown much love for the Mac Pro lately.

Availability for the Mercury Accelsior line starts now, though only the linked prices above are currently showing up online.

Source: OWC

Comments Locked


View All Comments

  • nathanddrews - Wednesday, April 18, 2012 - link

    Native PCIe SSDs seem like the wave of the future. Eliminate the SATA controller bottleneck...

  • havoti97 - Monday, April 23, 2012 - link

    PCIe is still too bulky. The future is mSATA. I'd rather have something more versatile. Once you upgrade, you can relegate the used SSD to a portable drive with a cheap encloser or your laptop.
  • ViperV990 - Wednesday, April 18, 2012 - link

    The blades don't appear to be mSATA. Are they proprietary?
  • eezip - Wednesday, April 18, 2012 - link

    To me, it looks like the same SSD as in the Macbook Air (http://www.anandtech.com/show/4527/2011-macbook-ai... And, being OWC, that makes sense. I suspect it's just a pair of MBA SSDs, running in RAID, from a PCIe controller.
  • Casper42 - Wednesday, April 18, 2012 - link

    And whats under the Heatsink on the left side?
    Its not like AT to forget that kind of information.

    is it a PCIe Bridge?, Is it a RAID controller? etc?
  • Penti - Wednesday, April 18, 2012 - link

    It's a Marvell SATA-controller. As the SSD's are 6Gbps SATA SSDs it's simply a 6Gbps SATA controller on PCIe.
  • Kevin G - Tuesday, April 24, 2012 - link

    Good eye. Here is the product page for OWC's MacBook Air SSD upgrades:


    They likely are the same basic part, just rebranded for usage on the PCI-e adapter.
  • joevt - Sunday, May 27, 2012 - link

    OWC says they are a different form factor than the MacBook Air SSDs.
    thessdreview.com says the Accelsior uses mPCIe boards.
  • PCTC2 - Wednesday, April 18, 2012 - link

    They look like the MacBook Air sticks, but shorter.
  • Casper42 - Wednesday, April 18, 2012 - link

    Good Eye. I went and played with some pictures of this new drive and the one for the MBA and sure enough the new one seems to be a little shorter.

    Ratio of the drive in the MBA (after lopping off the connector so you have a perfect rectangle) is about 4.3:1
    Similar Ratio of the drive on the Accelsior is about 3.8:1

    After looking at the pics a little closer, it just looks like they refined their PCB design. The Toshiba NAND packages are closer together on the new stuff than on the previous one. Perhaps they were aiming to meet the PCIe Half Length Specification so they can be validated as a Half height, Half Length card.

Log in

Don't have an account? Sign up now