Groups > comp.sys.mac.hardware.storage > #1358

Re: Is it me or are there many unreliable USB flash drives?

From	not@telling.you.invalid (Computer Nerd Kev)
Newsgroups	comp.sys.mac.hardware.storage, comp.sys.ibm.pc.hardware.storage
Subject	Re: Is it me or are there many unreliable USB flash drives?
Date	2016-10-22 21:22 +0000
Organization	Aioe.org NNTP Server
Message-ID	<nuglb2$us$1@gioia.aioe.org> (permalink)
References	(6 earlier) <e6r0lnFfurnU1@mid.individual.net> <QLydnR2Q1eAPgpTFnZ2dnUU7-VvNnZ2d@earthlink.com> <nubc4e$1t69$1@gioia.aioe.org> <nue22s$bg9$1@gioia.aioe.org> <211020161746161588%nospam@nospam.invalid>

Cross-posted to 2 groups.

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In comp.sys.ibm.pc.hardware.storage nospam <nospam@nospam.invalid> wrote:
> In article <nue22s$bg9$1@gioia.aioe.org>, Computer Nerd Kev
> <not@telling.you.invalid> wrote:
> 
>> 
>> There are USB voltage meters sold cheaply on Ebay to show if the
>> USB voltage from a computer is too high/low. If the USB voltage
>> was far too high, the extra energy would cause excessive heating
>> of the drive.
> 
> if the voltage was too high, not only would it not be usb compliant,
> but it would likely fry anything plugged into it, which is expecting a
> regulated 5v.

I don't mean by design (although anything's possible with Chinese
knock-off stuff, if that's involved), I mean due to a failure of
the computer hardware.

Now the 5V at the USB ports being high would often only make sense
if they were supplied by a separate line from the power supply. If
the internal computer components and the USB ports were both
subjected to a failure of the 5V voltage regulation, it would
be very likely to destroy the computer without the user having
any time to worry about their USB accessories.

Most desktop PCs have standard power supplies that provide the
USB 5V from the same lines as everything else, so it is unlikely
that an over-voltage situation would only affect the USB ports.

A laptop, however, may have a separate power supply circuit for
the USB 5V. If this failed, and supplied too high a voltage, it
may not sevierely affect the normal operation of the computer.

A power-boosted USB hub with a faulty or incorrectly specified
mains adapter powering it could also be a culprit.

> the amount of current sourced is limited by what the device
> negotiates from the host.

Current limiting only protects against an over-voltage situation
if the device requires more than the minimum current limit (500mA)
to be damaged. If an IC in the memory stick normally draws 20mA
at 5V, it may draw 28mA at 7V (this based on rough calculations:
5V / 0.02A = 250R   7V / 250R = 0.028A, but it proves the point),
however the IC may only be rated to sustain 5.5V, so it may be
damaged while only consuming 28mA. The rest of the components
in the memory stick will also be drawing additional power, but
you see that the total power draw is not increased enough to
hit the 500mA maximum if the stick normally draws, say, 100mA?

>> Another possibility, if you only ever use one USB port (or a group
>> of similarly affected ones) for testing these memory sticks, is
>> that a high resistance in the computer's USB socket is causing
>> the _socket_ to heat up, and the heat is being transferred
>> to the drives themselves via the USB connector. Here, not only
>> the heat, but also the coresponding reduced power to the memory
>> stick, may induce irrecoverable write errors or other failures.
> 
> unlikely.

Such failures are known to occour due to strain on solder joints
causing them to break, or joints that weren't correctly soldered
in the first place. It is a less common failure, but it's also
uncommon to consume large quantities of memory sticks.

-- 
__          __
#_ < |\| |< _#

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Is it me or are there many unreliable USB flash drives? ANTant@zimage.com (Ant) - 2016-10-17 16:03 -0500
  Re: Is it me or are there many unreliable USB flash drives? Mark Perkins <mark@none.invalid> - 2016-10-18 04:04 -0500
    Re: Is it me or are there many unreliable USB flash drives? ANTant@zimage.com (Ant) - 2016-10-18 16:27 -0500
  Re: Is it me or are there many unreliable USB flash drives? Doc O'Leary  <droleary@2015usenet1.subsume.com> - 2016-10-18 15:23 +0000
    Re: Is it me or are there many unreliable USB flash drives? "Happy.Hobo" <Happy.Hobo@Spam.Invalid> - 2016-10-18 12:13 -0500
      Re: Is it me or are there many unreliable USB flash drives? ANTant@zimage.com (Ant) - 2016-10-18 16:28 -0500
        Re: Is it me or are there many unreliable USB flash drives? "Happy.Hobo" <Happy.Hobo@Spam.Invalid> - 2016-10-19 00:15 -0500
          Re: Is it me or are there many unreliable USB flash drives? ANTant@zimage.com (Ant) - 2016-10-19 17:40 -0500
            Re: Is it me or are there many unreliable USB flash drives? "Happy.Hobo" <Happy.Hobo@Spam.Invalid> - 2016-10-19 17:52 -0500
              Re: Is it me or are there many unreliable USB flash drives? ANTant@zimage.com (Ant) - 2016-10-19 18:11 -0500
              Re: Is it me or are there many unreliable USB flash drives? Lewis <g.kreme@gmail.com.dontsendmecopies> - 2016-10-20 04:19 +0000
    Re: Is it me or are there many unreliable USB flash drives? Your Name <YourName@YourISP.com> - 2016-10-19 09:13 +1300
      Re: Is it me or are there many unreliable USB flash drives? not@telling.you.invalid (Computer Nerd Kev) - 2016-10-18 21:15 +0000
        Re: Is it me or are there many unreliable USB flash drives? ANTant@zimage.com (Ant) - 2016-10-18 16:51 -0500
          Re: Is it me or are there many unreliable USB flash drives? nospam <nospam@nospam.invalid> - 2016-10-18 17:52 -0400
            Re: Is it me or are there many unreliable USB flash drives? Doc O'Leary  <droleary@2015usenet1.subsume.com> - 2016-10-19 15:41 +0000
              Re: Is it me or are there many unreliable USB flash drives? nospam <nospam@nospam.invalid> - 2016-10-19 11:49 -0400
                Re: Is it me or are there many unreliable USB flash drives? ANTant@zimage.com (Ant) - 2016-10-19 17:42 -0500
          Re: Is it me or are there many unreliable USB flash drives? "Rod Speed" <rod.speed.aaa@gmail.com> - 2016-10-19 16:05 +1100
      Re: Is it me or are there many unreliable USB flash drives? ANTant@zimage.com (Ant) - 2016-10-18 16:32 -0500
        Re: Is it me or are there many unreliable USB flash drives? Your Name <YourName@YourISP.com> - 2016-10-19 13:28 +1300
          Re: Is it me or are there many unreliable USB flash drives? nospam <nospam@nospam.invalid> - 2016-10-18 20:41 -0400
        Re: Is it me or are there many unreliable USB flash drives? "Rod Speed" <rod.speed.aaa@gmail.com> - 2016-10-19 15:48 +1100
          Re: Is it me or are there many unreliable USB flash drives? ANTant@zimage.com (Ant) - 2016-10-19 17:50 -0500
            Re: Is it me or are there many unreliable USB flash drives? "Rod Speed" <rod.speed.aaa@gmail.com> - 2016-10-20 15:48 +1100
              Re: Is it me or are there many unreliable USB flash drives? ANTant@zimage.com (Ant) - 2016-10-20 14:48 -0500
                Re: Is it me or are there many unreliable USB flash drives? not@telling.you.invalid (Computer Nerd Kev) - 2016-10-20 21:14 +0000
                Re: Is it me or are there many unreliable USB flash drives? not@telling.you.invalid (Computer Nerd Kev) - 2016-10-21 21:41 +0000
                Re: Is it me or are there many unreliable USB flash drives? nospam <nospam@nospam.invalid> - 2016-10-21 17:46 -0400
                Re: Is it me or are there many unreliable USB flash drives? ANTant@zimage.com (Ant) - 2016-10-21 17:23 -0500
                Re: Is it me or are there many unreliable USB flash drives? nospam <nospam@nospam.invalid> - 2016-10-21 18:27 -0400
                Re: Is it me or are there many unreliable USB flash drives? ANTant@zimage.com (Ant) - 2016-10-21 18:05 -0500
                Re: Is it me or are there many unreliable USB flash drives? not@telling.you.invalid (Computer Nerd Kev) - 2016-10-22 21:26 +0000
                Re: Is it me or are there many unreliable USB flash drives? not@telling.you.invalid (Computer Nerd Kev) - 2016-10-22 21:27 +0000
                Re: Is it me or are there many unreliable USB flash drives? ANTant@zimage.com (Ant) - 2016-10-22 17:37 -0500
                Re: Is it me or are there many unreliable USB flash drives? Your Name <YourName@YourISP.com> - 2016-10-23 14:16 +1300
                Re: Is it me or are there many unreliable USB flash drives? not@telling.you.invalid (Computer Nerd Kev) - 2016-10-24 01:36 +0000
                Re: Is it me or are there many unreliable USB flash drives? nospam <nospam@nospam.invalid> - 2016-10-23 22:03 -0400
                Re: Is it me or are there many unreliable USB flash drives? "Rod Speed" <rod.speed.aaa@gmail.com> - 2016-10-24 13:54 +1100
                Re: Is it me or are there many unreliable USB flash drives? Doc O'Leary  <droleary@2015usenet1.subsume.com> - 2016-10-24 15:52 +0000
                Re: Is it me or are there many unreliable USB flash drives? nospam <nospam@nospam.invalid> - 2016-10-24 21:01 -0400
                Re: Is it me or are there many unreliable USB flash drives? Doc O'Leary  <droleary@2015usenet1.subsume.com> - 2016-10-25 15:56 +0000
                Re: Is it me or are there many unreliable USB flash drives? nospam <nospam@nospam.invalid> - 2016-10-25 12:33 -0400
                Re: Is it me or are there many unreliable USB flash drives? Doc O'Leary  <droleary@2015usenet1.subsume.com> - 2016-10-26 17:34 +0000
                Re: Is it me or are there many unreliable USB flash drives? "Happy.Hobo" <Happy.Hobo@Spam.Invalid> - 2016-10-26 13:59 -0500
                Re: Is it me or are there many unreliable USB flash drives? Lewis <g.kreme@gmail.com.dontsendmecopies> - 2016-10-27 00:13 +0000
                Re: Is it me or are there many unreliable USB flash drives? nospam <nospam@nospam.invalid> - 2016-10-26 23:19 -0400
                Re: Is it me or are there many unreliable USB flash drives? Lewis <g.kreme@gmail.com.dontsendmecopies> - 2016-10-26 00:09 +0000
                Re: Is it me or are there many unreliable USB flash drives? not@telling.you.invalid (Computer Nerd Kev) - 2016-10-22 21:22 +0000
                Re: Is it me or are there many unreliable USB flash drives? "Rod Speed" <rod.speed.aaa@gmail.com> - 2016-10-24 11:43 +1100
                Re: Is it me or are there many unreliable USB flash drives? not@telling.you.invalid (Computer Nerd Kev) - 2016-10-24 01:31 +0000
                Re: Is it me or are there many unreliable USB flash drives? nospam <nospam@nospam.invalid> - 2016-10-23 22:03 -0400
                Re: Is it me or are there many unreliable USB flash drives? "Rod Speed" <rod.speed.aaa@gmail.com> - 2016-10-24 13:51 +1100
                Re: Is it me or are there many unreliable USB flash drives? not@telling.you.invalid (Computer Nerd Kev) - 2016-10-24 21:42 +0000
                Re: Is it me or are there many unreliable USB flash drives? "Rod Speed" <rod.speed.aaa@gmail.com> - 2016-10-26 06:59 +1100
                Re: Is it me or are there many unreliable USB flash drives? "Happy.Hobo" <Happy.Hobo@Spam.Invalid> - 2016-10-23 23:52 -0500
                Re: Is it me or are there many unreliable USB flash drives? nospam <nospam@nospam.invalid> - 2016-10-23 20:53 -0400
                Re: Is it me or are there many unreliable USB flash drives? not@telling.you.invalid (Computer Nerd Kev) - 2016-10-24 01:49 +0000
                Re: Is it me or are there many unreliable USB flash drives? nospam <nospam@nospam.invalid> - 2016-10-23 22:03 -0400
                Re: Is it me or are there many unreliable USB flash drives? not@telling.you.invalid (Computer Nerd Kev) - 2016-10-24 21:54 +0000
                Re: Is it me or are there many unreliable USB flash drives? nospam <nospam@nospam.invalid> - 2016-10-24 21:01 -0400
                Re: Is it me or are there many unreliable USB flash drives? ANTant@zimage.com (Ant) - 2016-10-24 23:00 -0500
                Re: Is it me or are there many unreliable USB flash drives? nospam <nospam@nospam.invalid> - 2016-10-25 00:10 -0400
                Re: Is it me or are there many unreliable USB flash drives? ANTant@zimage.com (Ant) - 2016-10-24 23:11 -0500
                Re: Is it me or are there many unreliable USB flash drives? not@telling.you.invalid (Computer Nerd Kev) - 2016-10-25 21:14 +0000
                Re: Is it me or are there many unreliable USB flash drives? Your Name <YourName@YourISP.com> - 2016-10-21 13:50 +1300
                Re: Is it me or are there many unreliable USB flash drives? nospam <nospam@nospam.invalid> - 2016-10-20 21:32 -0400
                Re: Is it me or are there many unreliable USB flash drives? Lewis <g.kreme@gmail.com.dontsendmecopies> - 2016-10-21 08:53 +0000
                Re: Is it me or are there many unreliable USB flash drives? "Rod Speed" <rod.speed.aaa@gmail.com> - 2016-10-22 10:05 +1100
                Re: Is it me or are there many unreliable USB flash drives? "Rod Speed" <rod.speed.aaa@gmail.com> - 2016-10-22 10:03 +1100
            Re: Is it me or are there many unreliable USB flash drives? Jolly Roger <jollyroger@pobox.com> - 2016-10-20 15:30 +0000
              Re: Is it me or are there many unreliable USB flash drives? ANTant@zimage.com (Ant) - 2016-10-20 15:02 -0500
                Re: Is it me or are there many unreliable USB flash drives? Jolly Roger <jollyroger@pobox.com> - 2016-10-20 20:08 +0000
  Re: Is it me or are there many unreliable USB flash drives? "Rod Speed" <rod.speed.aaa@gmail.com> - 2016-10-19 05:09 +1100
    Re: Is it me or are there many unreliable USB flash drives? ANTant@zimage.com (Ant) - 2016-10-18 16:48 -0500
      Re: Is it me or are there many unreliable USB flash drives? Your Name <YourName@YourISP.com> - 2016-10-19 13:32 +1300
        Re: Is it me or are there many unreliable USB flash drives? nospam <nospam@nospam.invalid> - 2016-10-18 20:41 -0400
      Re: Is it me or are there many unreliable USB flash drives? Jolly Roger <jollyroger@pobox.com> - 2016-10-19 00:38 +0000
        Re: Is it me or are there many unreliable USB flash drives? ANTant@zimage.com (Ant) - 2016-10-18 21:30 -0500
          Re: Is it me or are there many unreliable USB flash drives? Jolly Roger <jollyroger@pobox.com> - 2016-10-19 15:50 +0000
            Re: Is it me or are there many unreliable USB flash drives? "Rod Speed" <rod.speed.aaa@gmail.com> - 2016-10-20 05:01 +1100
        Re: Is it me or are there many unreliable USB flash drives? "Rod Speed" <rod.speed.aaa@gmail.com> - 2016-10-19 16:08 +1100
      Re: Is it me or are there many unreliable USB flash drives? "Rod Speed" <rod.speed.aaa@gmail.com> - 2016-10-19 16:02 +1100
        Re: Is it me or are there many unreliable USB flash drives? ANTant@zimage.com (Ant) - 2016-10-19 18:10 -0500
          Re: Is it me or are there many unreliable USB flash drives? "Rod Speed" <rod.speed.aaa@gmail.com> - 2016-10-20 16:01 +1100
  Re: Is it me or are there many unreliable USB flash drives? Ed Light <nobody@nobody.there> - 2016-10-24 16:11 -0700
    Re: Is it me or are there many unreliable USB flash drives? ANTant@zimage.com (Ant) - 2016-10-24 23:01 -0500
  Re: Is it me or are there many unreliable USB flash drives? Ed Light <nobody@nobody.there> - 2016-10-24 16:16 -0700
  Re: Is it me or are there many unreliable USB flash drives? Ed Light <nobody@nobody.there> - 2016-10-24 16:19 -0700
    Re: Is it me or are there many unreliable USB flash drives? ANTant@zimage.com (Ant) - 2016-10-24 23:02 -0500
      Re: Is it me or are there many unreliable USB flash drives? Ed Light <nobody@nobody.there> - 2016-10-24 21:38 -0700

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