U.2 SSD's in cMP? (Classic Mac Pro)

Discussion in 'Mac Pro' started by LAHegarty, Dec 26, 2016.

Tags:
  1. LAHegarty macrumors member

    LAHegarty

    Joined:
    Aug 17, 2013
    Location:
    York, UK.
  2. Slash-2CPU macrumors member

    Joined:
    Dec 14, 2016
    Location:
    New Orleans, USA
    #2
    m.2, yes.

    Samsung XP941 and SM951(AHCI version) are bootable. Any dumb passthrough PCIe x4 carrier card will work.

    Any NVMe m.2 drive, such as Samsung 950 PRO, Intel 600p, or Plextor M8Pe is not bootable. To use as NVMe as storage requires IONVMeFamily.kext, a 3rd party driver. Freely available, but requires a little effort to make it work.

    Unless you need >512GB boot drive or what you're doing is very latency-sensitive to the point that NVMe would provide meaningful benefit, the 512GB SM951 AHCI is it. Part # MZHPV512HDGL . The drive will max out at 1340-1400MB/s read/write with latency that is second to none for a cMP boot drive.

    You can find em for $200-250, lightly used by some PC gamer type if you have time and patience.

    AHCI = cMP bootable
    NVMe = cMP non-bootable
     
  3. AidenShaw macrumors P6

    AidenShaw

    Joined:
    Feb 8, 2003
    Location:
    The Peninsula
    #3
    Also note that NVMe isn't a lot faster than AHCI for a lot of cases (compared to PCIe AHCI).

    NVMe only shines if you have a lot of parallelism - so it's great for busy servers, but kind of a letdown for single user workstations.
     
  4. Slash-2CPU macrumors member

    Joined:
    Dec 14, 2016
    Location:
    New Orleans, USA
    #4
    Exactly this. Going from Samsung AHCI XP941 to NVMe 950 Pro on my Win7 workstation was barely noticeable unless I'm doing 16 threads, 8 cores, and 9*10^10 data points, in which case it screams. Linear R-W difference is not much.
     

Share This Page