<div dir="ltr"><div>This was a set of offlist messages that I'm responding to on-list because they're relevant. I've removed the identifying info from the person responding to the OP since I didn't ask for permission. But then again, I didn't ask Bob's permission either. Tough. Deal with it. ;-)</div>
<div><br></div><div><br></div>Just to clarify/reinforce this a bit, don't use anything other than Spinrite Level 1 or 2. DEFINITELY NOT higher than 2 though. Level 3 and above will write to the drive, which is detrimental to SSDs. Essentially the reads Spinrite does will trigger the SSD's internal error correcting by forcing it to read each part of the SSD. If possible, any bad spots detected by the ssd will be relocated or re-written.<div>
<br></div><div>What I've come to find as the downside to SSDs vs traditional spinning drives though is the way they tend to fail. So far of the handful of SSDs I've had fail, every one of them was working one minute and then not the next. Not a single one has faded out slowly with bad sectors. At least with traditional drives sometimes you get a drive that up and dies on you, but more often than not its the platters that wear out and Spinrite can come to the rescue. Doesn't seem to be the case with SSDs. All told, though, I still hugely prefer SSDs over traditional drives.</div>
<div><br></div><div><div>About memory tests: I've learned a few things about RAM and come to respect it even more. For starters I use memtest86+ to test RAM and let it run for as long as possible, preferably days, but at least several passes. memtest86+ uses various patterns to test the bits in various ways. This is necessary because it's possible for a single pattern to actually miss bad bits. For instance, a simple example would be writing all 11111111's out could miss the fact that a bit is stuck on 1 and won't flip to 0. So, the obvious thing to do is then write out all 00000000's? That could catch out a bit that's stuck on 1. But what about a bit that's stuck to it's neighbor? memtest does a really good job at testing the RAM, but even a current computer with a current normal amount of RAM can actually take hours to complete a full pass of all the various pattern iterations necessary to adequately test the RAM. It's also quite possible that a bit will be ok on the first couple of passes but then fail on a later pass.</div>
</div><div><br></div><div>When we think of RAM failures, we tend to think of the more obvious failures...like when Windows BSODs or a kernel panics because the RAM has a significant enough patch of bad bits in the right spots that an important binary wigs out. But it can actually be a lot more insidious than that. Sometimes, the bad bits are just "insignificant" enough that the OS doesn't obviously fail, but bad bits are still creeping into your environment. It could be a long time before something really bad happens that makes you think there might be a hardware problem. In the meantime, that uber-important spreadsheet which you neglected to back up is slowly getting clobbered. Those are the worst. It's also why ECC RAM is so important on servers. The extra bits help to detect any stuck bits and halt the system before the bad data creeps in.</div>
<div><br></div><div><br></div><div><br></div><div><span style="color:rgb(37,37,37);font-family:sans-serif;font-size:14px;line-height:22.399999618530273px">From Wikipedia on Spinrite:</span></div><div><span style="color:rgb(37,37,37);font-family:sans-serif;font-size:14px;line-height:22.399999618530273px">Spinrite can be run and can be effective on SSDs, but running in a higher-level mode than 1 or 2 is detrimental, as it wears the SSD by writing to it unnecessarily. In episode 194 of the podcast </span><a href="http://en.wikipedia.org/wiki/Security_Now!" title="Security Now!" class="" style="text-decoration:none;color:rgb(11,0,128);font-family:sans-serif;font-size:14px;line-height:22.399999618530273px;background-image:none;background-repeat:initial">Security Now!</a><span style="color:rgb(37,37,37);font-family:sans-serif;font-size:14px;line-height:22.399999618530273px"> Gibson said that he could "see absolutely no possible benefit to running SpinRite on a solid-state drive" and later "SpinRite is all about mechanics and magnetics, neither of which exist, by design, in an SSD".</span><sup id="cite_ref-10" class="" style="line-height:1;color:rgb(37,37,37);font-family:sans-serif"><a href="http://en.wikipedia.org/wiki/SpinRite#cite_note-10" style="text-decoration:none;color:rgb(11,0,128);white-space:nowrap;background:none">[10]</a></sup><span style="color:rgb(37,37,37);font-family:sans-serif;font-size:14px;line-height:22.399999618530273px"> In episode 338 Gibson clarified "it is actually detrimental because [solid-state drives] don't like to be written", but also pointing out that a read-only run could be beneficial: "SpinRite's Level 1 is a read-only scan, and doing that on an SSD makes a lot of sense. Do a read-only scan of an SSD, it'll show the SSD's controller that it's got a problem reading a sector, and then it'll map that out or rewrite it in order to strengthen that sector, if possible. So that ends up being a value for SpinRite on solid-state drives." </span><sup id="cite_ref-11" class="" style="line-height:1;color:rgb(37,37,37);font-family:sans-serif"><a href="http://en.wikipedia.org/wiki/SpinRite#cite_note-11" style="text-decoration:none;color:rgb(11,0,128);white-space:nowrap;background:none">[11]</a></sup><span style="color:rgb(37,37,37);font-family:sans-serif;font-size:14px;line-height:22.399999618530273px">Also, Gibson posted on his website that "SpinRite is seeing many successes [...] with non-spinning solid-state (thumb) drives!".</span><br>
</div><div><br></div><div><br></div><div>Hope someone finds this useful.</div><div>Chad</div><div><br></div><div><br></div><div class="gmail_extra"><div>______________________________<br><b>Chad Neeper</b><br><font size="1">Senior Systems Engineer</font><br>
<br><b>Level 9 Networks</b><br><font size="1">740-548-8070 (voice)<br>866-214-6607 (fax)</font><br><br><font size="1"><i>Full LAN/WAN consulting services -- Specialized in libraries and schools</i></font><br></div>
<br><br><div class="gmail_quote">On Thu, Jul 31, 2014 at 12:02 PM, Bob Neeper <span dir="ltr"><<a href="mailto:neeperro@oplin.org" target="_blank">neeperro@oplin.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">
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<div>Good suggestion about SpinRite, in read
only mode.<br>
Not sure if it would work though if the hard drive was truly not
found by the BIOS.<br>
Had some mechanical drives that I don't think it could see.<br>
<br>
Anyway I did another data backup, ran the Intel SSD Toolbox which
showed the C: part as good.<br>
Half the SSD is Truecrypte'd and Toolbox doesn't like it.<br>
Updated Toobox and ran it again.<br>
<br>
Rebooted and all is okay.<br>
<br>
I will pretend it was a fluke due to having to force the laptop
down last night for some reason.<br>
<br>
But I think I'll try to find my original HD tonight and image it.<br>
<br>
Bob<br>
<br>
On 7/31/2014 9:19 AM, someone wrote:<br>
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<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)">Oh
no!!!! Did you try running SpinRite on level 2 or 3? It
supposedly can repair errors even on SSDs… When watching the
memory test, I invariably have the same thought: “This is
silly.”<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"><u></u> <u></u></span></p>
<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)">Drink
coffee, and cross your fingers!<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"><u></u> </span></p></div></blockquote>
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