Results from a couple computers

  • SpinRite v6.1 Release #3
    The 3rd release of SpinRite v6.1 is published and may be obtained by all SpinRite v6.0 owners at the SpinRite v6.1 Pre-Release page. (SpinRite will shortly be officially updated to v6.1 so this page will be renamed.) The primary new feature, and the reason for this release, was the discovery of memory problems in some systems that were affecting SpinRite's operation. So SpinRite now incorporates a built-in test of the system's memory. For the full story, please see this page in the "Pre-Release Announcements & Feedback" forum.
  • Be sure to checkout “Tips & Tricks”
    Dear Guest Visitor → Once you register and log-in please checkout the “Tips & Tricks” page for some very handy tips!

  • BootAble – FreeDOS boot testing freeware

    To obtain direct, low-level access to a system's mass storage drives, SpinRite runs under a GRC-customized version of FreeDOS which has been modified to add compatibility with all file systems. In order to run SpinRite it must first be possible to boot FreeDOS.

    GRC's “BootAble” freeware allows anyone to easily create BIOS-bootable media in order to workout and confirm the details of getting a machine to boot FreeDOS through a BIOS. Once the means of doing that has been determined, the media created by SpinRite can be booted and run in the same way.

    The participants here, who have taken the time to share their knowledge and experience, their successes and some frustrations with booting their computers into FreeDOS, have created a valuable knowledgebase which will benefit everyone who follows.

    You may click on the image to the right to obtain your own copy of BootAble. Then use the knowledge and experience documented here to boot your computer(s) into FreeDOS. And please do not hesitate to ask questions – nowhere else can better answers be found.

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New member
Oct 20, 2020
The first is a home-built system with a 1TB hard drive and a 250GB SSD. The second is a Toshiba laptop with a slow 250GB hard drive and a 250GB SSD.

Driv Size  Drive Identity     Location:    0      25%     50%     75%     100
---- ----- ---------------------------- ------- ------- ------- ------- -------
 81  250GB WDC WDS250G2B0A-00SM50        267.5   269.6   271.7   273.1   273.4
 82  1.0TB ST31000524AS                   82.0   117.5   106.7    87.9    63.6

                  Benchmarked: Sunday, 2020-12-27 at 11:35

   NOTE: A faster SATA drive is attached to a slower SATA link. You may add
         the /ident command-line option to display and identify the drive.

Driv Size  Drive Identity     Location:    0      25%     50%     75%     100
---- ----- ---------------------------- ------- ------- ------- ------- -------
 81  250GB TOSHIBA MK2576GSX              72.1    65.6    59.2    49.4    35.6
 82  250GB CT250MX500SSD1                237.7   229.6   232.0   270.8   236.8

                  Benchmarked: Sunday, 2020-12-27 at 11:56
Hi, thanks for posting your results!

Your WDC drive is looking pretty good!

Interesting that Readspeed mentions the slower SATA link in the laptop, but the SSD speeds don't seem to be capped at any particular point. I'm guessing it must be SATA II in the laptop? But I don't know exactly what the limit on that would be.

A lot of drives seem to max out at around 543MB/s, so I'm guessing the practical limit for SATA III may be around there?

SATA II should hypothetically be about half that speed, so I guess about 272MB/s might be the practical limit?
Last edited:
SATA II = 300MB/sec, SATA III = 600MB/sec, but there is a certain amount of overhead involved, so maximum actual data speeds are about 90% of that, so subtract about 30MB/sec for SATA II and 60 MB/sec for SATA III.
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