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Groups > comp.sys.mac.hardware.storage > #1370
| 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 | 2016-10-24 01:49 +0000 |
| Organization | Aioe.org NNTP Server |
| Message-ID | <nujpbk$au4$1@gioia.aioe.org> (permalink) |
| References | (8 earlier) <nubc4e$1t69$1@gioia.aioe.org> <nue22s$bg9$1@gioia.aioe.org> <211020161746161588%nospam@nospam.invalid> <nuglb2$us$1@gioia.aioe.org> <231020162053440081%nospam@nospam.invalid> |
Cross-posted to 2 groups.
In comp.sys.ibm.pc.hardware.storage nospam <nospam@nospam.invalid> wrote: > In article <nuglb2$us$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. > > if the internal power supply failed then computer wouldn't work, not > just the ports. > >> 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. > > exactly the point. > >> 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. > > no. Yes. If the 5V supply circuit was built separately for use by the relatively high current USB devices, it's failure (in this way) would not stop the computer operating. In some cases it might (I won't spend the time spelling it out), but if no USB devices are connected, it won't. >> A power-boosted USB hub with a faulty or incorrectly specified >> mains adapter powering it could also be a culprit. > > no hub was used. Known now, yes. >> > 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? > > usb devices don't work that way. OK, so the device can specify roughly the current it needs via the USB protocol, which if you're lucky will be respected by the computer hardware. The current specification isn't accurate enough to prevent damage though, for the reason shown above. The current increase as voltage is increased isn't great enough to trip the limiting. >> >> 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. > > broken joints don't get hot. they simply don't work. Sometimes they simply form a high resistance. Look it up - dry joints. >> It is a less common failure, but it's also >> uncommon to consume large quantities of memory sticks. > > it's not uncommon at all. memory sticks are cheap enough to be > considered disposable. sometimes they're even given away for free. As I remember it, OP figures that he's bought good ones - hence his confusion about the cause of the failure rate. -- __ __ #_ < |\| |< _#
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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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