SanDisk Extreme Portable SSD Speed

Portable SSD Portable | Extreme | Extreme Pro SSD
1

I read in some reviews this drive should be around 500MB read / write, I think I’m getting closer to 40, I ran CrystalDiskMark on it with the results below. I’m wondering A) am I getting what I should expect for speeds? B) To get expected speeds will a standard usb-c cable suffice? The original cable was lost so I’m using one from a recent cell phone. Its also a thunderbolt compatible port, but I don’t think that is relevant. If the problem may be the cable, could someone be so kind as to recommend one that should work well for this. Thanks.

CrystalDiskMark 6.0.2 x64 (C) 2007-2018 hiyohiyo
Crystal Dew World : https://crystalmark.info/

  • MB/s = 1,000,000 bytes/s [SATA/600 = 600,000,000 bytes/s]

  • KB = 1000 bytes, KiB = 1024 bytes

    Sequential Read (Q= 32,T= 1) : 39.949 MB/s
    Sequential Write (Q= 32,T= 1) : 43.698 MB/s
    Random Read 4KiB (Q= 8,T= 8) : 27.784 MB/s [ 6783.2 IOPS]
    Random Write 4KiB (Q= 8,T= 8) : 26.475 MB/s [ 6463.6 IOPS]
    Random Read 4KiB (Q= 32,T= 1) : 27.209 MB/s [ 6642.8 IOPS]
    Random Write 4KiB (Q= 32,T= 1) : 26.432 MB/s [ 6453.1 IOPS]
    Random Read 4KiB (Q= 1,T= 1) : 11.987 MB/s [ 2926.5 IOPS]
    Random Write 4KiB (Q= 1,T= 1) : 15.307 MB/s [ 3737.1 IOPS]

    Test : 100 MiB [D: 79.3% (738.3/931.5 GiB)] (x5) [Interval=5 sec]
    Date : 2020/07/13 2:55:00
    OS : Windows 10 Professional [10.0 Build 19041] (x64)

2

I’m using a 1tb Sandisk Extreme Pro V2 to bypass the extremely slow mechanical drive in my 2019 iMac. I am using a USB-C cable that came with ssd and plugging it into the USB-C/Thunderbolt 3 port. I’m getting 920 MB/sec. The first generation Pro normally gets around 450 MB/sec. with the same hookup. I believe you have a bad cable or other problem for sure.