I have had enough hard drives that I can make some sense about their reliability.
I have had a variety of SCSI drives, starting with 2gb 10mb/sec SCSI. Most are not currently in use.
I have had a variety of IDE drives. I have seen a few serious failures of drives that I have inherited. For all drives I have purchased, when there were problems, I could always copy most or all the files before the drive failed.
I have had several SATA drives so far.
I usually run my main computer 24x7. It is very well cooled. See Keeping Everything cool for details.
The full name is My Passport Essential SE. Purchased Jun-2011, bad blocks causing failure May-2015, 3 years 11 months. The drive comes with a 2 year warranty, and it was being used 24x7, so it is not unreasonable to have bad block errors after almost 4 years. I was able to remap the bad sectors. Once a hard drive has bad block errors, it is generally considered unreliable. Nov-25-2015 - While copying the data off of the hard drive onto a new hard drive, it produced a whole lot more errors. I was unable to successfully correct them. Now the disk randomly fails after a few minutes of use. Safe to say it is now toast.
I bought this drive around Jun-2006. About a month ago, my computer started acting funny. Sometimes it would freeze. Sometimes it would reboot. Eventually it got to the point where the hard drive would be detected by the BIOS but would go offline by the time windows booted. It turned out that I had the swap file on the drive, which was likely part of the reason for the funny symptoms. Now it has failed, and never goes online. I was unable to copy more than a few files from the drive before it went offline. Fortunately, I have a 3 month old backup, and nothing significant has changed. I sent it in for warranty replacement.
I recently bought four 500gb sataII hard drives to use in a raid array. I bought them because they were inexpensive and had a 3 year warranty. Though they are labeled MAXTOR STM3500630AS drives, they are really Seagate 7200.10 series drives (Seagate recently purchased Maxtor). When I built the raid array, it failed immediately. I thought the problem was the linux driver for the sata II controller chip. I was wrong. One of the drives kept failing, leaving the array. For debugging, I booted windows xp and I was able to format each drive and copy stuff to it. XP didn't complain, so I thought it was a linux problem. Shows how weak the error reporting of XP is...
As hard drives get denser and more complex, the ability to monitor them has also increased. There is a standard called "SMART" which means Self-Monitoring Analysis and Reporting Technology. It reports all kinds of data about hard drive health. Thanks to the help of the linux-ide kernel folks, and me learning more about linux ide/sata, raid, and SMART monitoring, I found out that one drive was quite sick, and returned a bunch of errors of "READ DMA". This started after 57 hours of being powered up. The other drive returned several "READ VERIFY SECTOR" errors after 11 hours of being powered up. I was able to get these errors using "smartctl -a", which is a linux program, (ported to windows) that monitors SMART parameters. I send the drives back for repair/replacement. They were replaced with 750gb recertified hard drives.
Well, a few months after I got the two replacement drives for the broken Maxtor drives I tried to build my new backup file server using four sata drives. Two were Maxtor, one was the recertified Seagate 750gb drive from above, and the other was a 500gb Hitachi drive I had lying around. I built the software raid 5 array, but I kept on having errors with the files I wrote. I switched almost everything - the power supply, the processors, the motherboard, the memory, but still the errors persisted. It was very confusing tracking down the problem. I suspected samba, the network card, the controller card software, and lots of other stuff. I eventually broke apart the raid array, and tested each drive separately. It turned out that three drives were perfect, and one wasn't. The fourth drive was one of the two Maxtor 500gb drives. Although there were no SMART errors, and it passed all of the Maxtor diagnostics, it still failed my test.
My test was to format the drive, and write sixteen big files. I happened to have dvd iso images for a linux distribution that I used for the files. Next, I generated a md5 checksum for the files and wrote it out. I then regenerated the md5 checksum, and it wasn't the same for several files. I am pretty sure that the bits didn't get switched on the disk, because when I generated more md5 checksums, they kept on changing. It was clear that I was getting disk read errors. There were between four and sixteen errors that I detected during reading of about 64 gigabits. Not a high error rate, but definitely a bad drive. I recommend running this test, or something like it on suspect hard drives. I got the replacement hard drive (a remanufactured 750gb), and I filled the disk with big files and ran the test a few times. No problems whatsoever. I am disappointed that none of the manufacturers tests showed this problem. On the other hand, they did replace the 3 failed drives with 750gb drives, so I got a total of 750gb for 'free'.
Well, three of the four Maxtor 500gb drives failed reasonably quickly after I bought them. It turns out I managed to store my most important files on the fourth one. About a month ago my computer started 'freezing'. At first it was only for a minute or two, but eventually the computer would freeze, and never unfreeze. I checked the SMART status of my drives, and one had a bunch of errors. Specifically read failures. I removed the drive, and no more failures. After much effort, I was able to copy all the files off the bad drive, onto other drives. It has been sent back for repair/replacement. Clearly some hard drives fail in batches.
Being paranoid (or prepared), I have md5sums for most of my files. I noticed that a bunch of md5sums had changed for files that I had not modified. It would seem that the hard drive flipped a few bits. I was able to recover all but two of the changed files, thanks to having several backup fileservers. Of course, it does no good to store corrupted files, so it is a good idea to check the files are ok, before backing them up. I wasn't always so clever, but I had multiple copies of the data, spread over a wide period of time. I have sent in the drive for RMA. It is amusing to note that I cannot run the Hitachi drive fitness test. It boots to DOS and I suspect my USB keyboard is not detected by the DOS drivers. It seems like it is time for Hitachi to use a more modern way to test hard drives.
This is a modern 3tb drive. It has a sata 3 interface (600 mb/sec). It has 3 platters. It was DOA. I sent it back and got a new one that seems to be working fine. It is quite odd, as it was sealed in the factory anti-static bag. Does Toshiba test the drives? Did it fail during shipping? I have never had a DOA hard drive before.
I bought 2 used Supermicro SATA racks. These hold 5 SATA drives in three 5.25 inch drive bays. There is a 92mm fan in the rear that cools the hard drives. This fan is about 32mm thick, rated at 0.31 amps, 2900 rpm, and 55.1 cfm. As expected, it moves lots of air and keeps the hard drives cool. What is interesting, is my 4 drive SCSI rack uses 3 tiny 40mm*10mm fans, with a total of about 15 cfm, and it can keep 15,000 rpm SCSI drives cool. I decided to install an inline fan speed controller in order to keep the fan noise down.
The instructions that come with the rack are decent, but leave much room for the imagination. The rack comes with 13 flat head screws, 24 round head screws, and 7 round head screws with lock washers. Now what are they all for? The hard drive rack looks like it should be using flat head screws, but with 4 screws per drive, and 5 drives, that should be 20 screws, but only 13 are provided. Clearly, some screws are for securing the rack in the computer. I would guess they are the ones with lock washers, but I would assume an even number, with the same on either side of the rack. If anyone knows the answer, please let me know.
If you don't use low profile screws on the drive trays, the drive rack is hard to insert. Don't force it, get low profile screws. The rack doesn't have any provision to stagger the spin up of the drives, unlike my SCSI drive rack. I called Supermicro, and they said their controller does it automatically. I guess if you don't have their controller, you are out of luck. It does have a fan rpm alarm and a temperature alarm which can be configured via jumpers on the back of the rack.
If you don't need hot swap, and you are happy with 4 drives per 3 5.25 inch drive bays, use a Coolermaster 4-in-3 module. It has a nice, big, quiet 120mm fan that does a great job of keeping the drives cool, and is much cheaper. If you get tired of opening the case and disconnecting all the drives data and power cables, this is a great product except for the noisy fan.
I have always had SCSI hard drives. I now use them for my operating system, not for general storage. They are typically smaller than IDE or SATA drives, but that isn't a problem as the OS doesn't need much space. If you want 10,000 rpm, SCSI used to be the only way to go, until Western Digital introduced the raptor drive. If you want 15,000 rpm, SCSI is still the only way to go. (The higher rpm's allow faster file access time, as the platter rotates faster). New things like command queuing for SATA has been around for many years in the SCSI world.
SCSI also has had the ability to hot-swap, that is remove and insert while the computer is running, which is a new thing for SATA. The hot swap SCSI drives have 80 pin connectors on the back of the hard drive. The 80 pins supply data (which is either 50 or 68 pins for SCSI), power, SCSI id, some led signals and the like. You can buy hard drive bays which hold multiple hard drives and allow them to be inserted or removed via hard drive trays which bolt to the hard drive. This way, you don't have to open the computer case to switch hard drives.
This has always sounded like a great idea to me, however they have some drawbacks. The first is they are generally expensive. The second is some do not allow enough air flow over the hard drives to keep them cool enough. A 15,000 rpm SCSI hard drive can easily draw 20 watts. I found a decent 4 hard drive bay SCSI hot swap rack made by Chieftec. It has may good features. Like any serious hard drive rack, you can delay the power up of the hard drives. Since they need peak power during spin up, when you turn your computer on, all the drives will start to spin up. This allows a delay before the drives in the rack spin up. (Some cheap SATA racks lack this feature). There are lights for each drive to indicate power and access. There is good airflow provided by 3 40mm exhaust fans. There is an alarm that sounds if the rack gets too hot or any fan fails. As for the bad, the front of the hard drive tray is plastic along with the lock that secures the tray. I did manage to break (and repair) one tray lock. There is no documentation online for this product, as it has been unavailable for several years.
Recently, the alarm has been sounding. You can reset it with a button, but it kept on sounding. I opened the case, and observed one of the fans was barely rotating. I looked up the fan specs and found it was a simple sleeve bearing fan with a rated life of 30k hours. I also looked at my hard drive temperature, and found though I only had 2 hard drives powered up, one was around 48C, which I don't like, especially since it was just idling. I switched the bottom fan (failed) with the top fan, and the temperature dropped to 44C which was better but not good. I ordered 3 fancy fans which had a bit more airflow, a superior bearing with 100k hour rated life, and were even quieter than the original fans. As soon as hey arrived, I swapped in the new fans for the old fans. Now all my hard drives are cool, and the alarm doesn't sound. The previously hot drive is now at 40C.
I have a Sony 4mm DAT drive. There is now a newer one, the SDT-9000, which is faster and has a higher capacity (what else is new?). It is reasonably reliable. I have had to send it back once, since it broke in a way that I don't recall.
Well it broke again 12/27/97. Did a full backup flawlessly, but refused to eject the tape. The manual eject button does no good, and when I send a SCSI command to eject, I get an error return. I am most unimpressed. I have probably made 20-30 tapes, and it has failed twice. I will send it back to Sony, and no doubt pay plenty. This drive is still listed on their web page, and people are still selling it, so I would guess it is still being made. Hope Sony can get my backup tape out... I now do not recommend this drive at all under any circumstances due to poor reliability.
Well it broke again Dec-24-1999. Backed up some data, then got a buncha errors, timeouts, and the like. And it was with new tape. So I traded it in with New Image International. They told me that the Sony sdt-7000, sdt-9000, and sdt-10000 have 'soft' heads, and when they go, the cost to fix the heads is about what the drive is worth. They said the HP DAT-8 was better, so I got it. I will eventually get a DLT drive, when they get cheaper and I get more money.
I have a Dazzle Universal 6 in 1 Reader. (Dazzle has since been acquired by Pinnacle). This is designed to read and write CompactFlash, IBM Microdrive, SmartMedia Card, MultiMedia Card/Secure Digital, and Memory Stick media. Sounds good, right? It actually works ok on Windows XP. On Windows 2000, when you install it, you hose up the operating system in a really major way. After much thrashing I was able to fix Windows the first two times I installed the operating system. The third time I installed Windows and the reader, I was unable to fix the OS. I spent many hours of hair pulling and swearing to no avail. I searched the dazzle web site for into to help, to no avail. I sent their tech support email, and I finally received a reply 8 days later (after making them weasel of the month). I have since upgraded to Windows XP, in order to have a working computer.
So in my experience, the best way to completely and irrevocable screw up Windows 2000, is to install a Dazzle reader. I have overcome many hardware and software problems in the past, but this is the worst by far. I cannot overemphasize the poor quality of the Dazzle software. I am used to software not working, or crashing, but breaking the operating system in a fatal way requires extra effort, and Dazzle has done it.
Here are my replies to their email. Their text in in italics. My editorializing is in [square brackets]:
Subject: Re: Windows 2000 professional [Incident: 030218-000454]
Recently you requested personal assistance from our on-line support center. Below is a summary of your request and our response.
We will assume your issue has been resolved if we do not hear from you within 168 hours.
Thank you for allowing us to be of service to you.
You may also update this question by replying to this message. Because your reply will be automatically processed, you MUST enter your reply in the space below. Text entered into any other part of this message will be discarded.
[===> Please enter your reply below this line <===]
Well, I don't have a USB card to add or remove. It is built
into my motherboard. Therefore, 2a, 2b, 2c, 2d, 2e, 2f are
I do have antivirus software running, Norton antivirus. I do have another Windows 2000 pro system correctly running on my machine. Since I cannot be without my OS for a week, I did a fresh OS install and used Windows XP pro. Since I didn't find anything on your FAQ (and I still can't find any entries with the word virus in them), and since it took you a week to reply to me, and since your product has always rendered windows 2000 useless, and since you didn't send email to my hotmail account as I asked (since I can't read email when my system is hosed), I have decided to make dazzle weasel of the month at weasel.com. See www.weasel.com for details.
So in that sense my problem is resolved. However your problem sure isn't resolved.
Have a nice day,
domain owner of weasel.com
PS: I really like the quote "I'm sure your questions are answered"
[===> Please enter your reply above this line <===]
If your issue remains unresolved, please update this question here.
Subject Windows 2000 professional
Response (Naveen)02/27/2003 05:09 AM
Thanks for your patience and your confidence in Dazzle.We are very sorry for this delayed feed back.We will make sure to give them in due time.
[I suspect that they replied at all because I made them weasel of the month, and sent their PR person an email about that. Can't prove it. I also like the sorry for the delayed feed back message. All of their email seems to have it as boiler-plate and for good reason.]
There could be numerous other reasons for the system reboot.
[The reason for the system reboot is that I rebooted the system. The problem is that the system won't finish booting up, not the 'system reboot'.]
Please go through the following and let us know if any of them help you out.
1.Please ensure there are no antivirus is installed and is running on the background.This might sometimes clash with the Installation.
[This is really useful. Since windows is so buggy I would think almost everyone is running some kind of antivirus program. And I searched their help system, and didn't find anything under virus or antivirus, nor does their installation mention it.]
2.The reason could be an IRQ clash.
a.shut down the system
b. remove the USB card
c.Start the system
d.Shut it down again
e.Insert the USB card
f.start the system
g.Insert the device with media
[If it were an IRQ clash, the other OS installations would likely not work also. Also I never mentioned a USB card. As most motherboards have USB now, this seems like useless at best advice.]
I'm sure your questions are answered.
[This is a really puzzling statement. Perhaps just odd english, but it seems wildly optimistic.]
Thanks in advance.
Have a great day!
Auto-Response02/18/2003 10:39 PM
, Thank you for your interest in your Dazzle* 6-in-1 Card Reader/Writer. Your issue is still unresolved and is being worked on by our staff. In the meantime, these Answers were automatically selected for your consideration. If your issue is addressed in our public Answers, a solution link should be listed below. If no solutions are listed or the solutions do not match your issue, there were no public Answers related to your issue. A Customer Service agent will be responding to you shortly. If one of the Answer links below resolves your issue, please close this incident.
> Please visit the following links:
Title: Optimal Computer Performance for PCs
Title: Drive letter assignment for USB Card Readers in Windows 2000 & XP on a LAN
Title: Safe ejection of removable media in Windows 2000
Title: Locating the part number for your Dazzle installation CD
Customer02/18/2003 10:39 PM
When I use the install cd and reboot my system, the system hangs. I tried the previous configuration, but that hangs also. I tried safe mode, and uninstalled the device, and then unplugged the device. I successfully uninstalled via the device manager. When I reboot into normal win 2000 sp3, the system hangs. I am really in a bad way now.
I remember similar problems when I did this the last time I installed win 2000, but I did something clever to successfully install the reader. Any ideas?
It would be ideal to send email to email@example.com, as it is difficult to read email, when I cannot boot my main computer.
Subject: Re: Windows 2000 professional [Incident: 030218-000454]
[===> Please enter your reply below this line <===]
I did read the ZiO! link, and it was somewhat useful. Too bad I couldn't find anything like it for the 6-in-1 reader when I was hosed up.
I am glad you like my website. I am sorry you don't feel in your heart of hearts that when a piece of hardware/software renders a computer unusable that they should be called weasel of the month. I have at least 10 computers here, and quite a wide variety of hardware. I have never had 3rd party software render my computer OS unusable before. I have modest skill writing software, with over 20 years of experience, as well as working on the very first e-commerce system, and I have never seen such damaging software. I would suggest a course in basic software engineering for your developers.
I find your message 'Give us one more try on Win2K.I'm sure you will find us good.' really amusing. Do you think I want to scrub my 15k RPM SCSI drive of a working OS (win XP) that took me well over 10 hours to install and load all the apps, just so I can re-install win 2000, and go through the process of patching it, and installing my apps, just for the privilege of wedging my system again (as it has done every time) with your system-destroying software? Do you know what a production system is? I run my main computer 24*7. I don't have time to reload a OS, nor do I feel that plugging in a new 15k RPM drive and loading win2000 is a really fun process.
Having to use the recovery console on win2000 should give you folks a clue that something is seriously wrong with your software. Fortunately, Microsoft included enough drivers with win XP that I don't have to use your death-inducing cd software installer.
If you folks want to pay me to test your software, I am happy to do so. I will get a dedicated machine to do so, so I won't disrupt my main computer operations. I have a variety of single and dual processor systems, with Intel and AMD chips and a variety of BIOS's and clock rates.
I also do software engineering consulting. My rates are reasonable.
[===> Please enter your reply above this line
If your issue remains unresolved, please update this question here.
Subject Windows 2000 professional
Response (Naveen)02/28/2003 06:09 AM
I understand your frustrations loud and clear.I perfectly justify them.The answers are some of them which have helped people who sounded the exact way your mail read.It sure has helped them.
We really want to help you out and make you feel that you did make a right choice on purchasing Dazzle.
Here are some notes on Win2000 Problems on Installation.
1.Please go through FAQ ID 1203
2.Title: During the ZiO! Installation I get a blank screen URL: http://scmmicro.custhelp.com/cgi-bin/scmmicro.cfg/php/enduser/std_adp.php?p_faqid=475&p_created=1003258931
P.S -I really like your creativity(I mean it!!!). and I did go through your website.But,Heart of hearts I feel we do not deserve that place.Give us one more try on Win2K.I'm sure you will find us good.I'm keeping this mail unresolved to make sure I will sort out your issue.
Customer02/27/2003 07:58 AM
[... repeated stuff deleted...]
This enclosure is USB as well as e-SATA. It has a power switch, as well as an I/O bracket and adapter from an internal SATA port, to provide an e-SATA port in case your motherboard doesn't have one. This enclosure has a very quiet cooling fan. It is very easy to install a hard drive, though there are a bunch of screws to contend with. In the interest of minimizing vibration, the hard drive secures with screws on the bottom, which are surrounded with silicone washers. Overall, I think this is the best 3.5" hard drive enclosure.
A basic SATA notebook drive enclosure. It has a led and what looks like a power connector. The instructions say it is for an external 5v power supply if needed. I put in a OCZ Vertex 3 SSD. The SSD is rated at 550mbytes/sec read and 500 mbytes/sec write. In the Bytecc enclosure, the highest speed I could get was 140 mbytes/sec read and 101 mbytes/sec write. I suspect the bottleneck is either with the SATA-USB3 converter chip, or my NEC based USB3 card. I did install the latest drivers for the USB3 card. It is faster than a thumb drive, but nowhere as fast as the SSD should be. Something is broken...
This enclosure is USB only. It has a power switch, a power LED, and an activity LED. There are some vents on the bottom, but they press against the top of the hard drive, and seem mostly useless. It is very easy to install a hard drive, unlike the Western Digital WD1200. It also takes up quite a bit of space with the 'X' shaped exterior. At least it puts an air gap around much of the hard drive to hopefully aid cooling.
I bought this drive because it had usb2 as well as firewire interfaces. After about 2 years it failed. Iomega replaced it with a refurbished drive which broke after a few months. I was using this drive 24x7, which is a bit harsh, however it was in an air conditioned environment. I was unimpressed with the refurbished drive. When the refurbished drive failed, it failed intermittently, which produced some quite amusing Linux kernel messages. Select versions of the kernel produced 'oops' errors which I reported. Most external drives have a 2 or 3 year warranty. I recommend buying an enclosure and an internal drive to get a longer warranty.
This was my first external hard drive. It features USB as well as firewire. It has a 120gb 7200 rpm IDE hard drive. It has a power LED as well as an activity LED. One missing feature is a power switch. You have to yank a cord to turn it off, which is a hassle. I used it exclusively with the firewire interface, which worked quite well. After the 1 year warranty ran out, I opened it up, and put in a 200gb hard drive. The case was not designed for this. Two screws that have to be removed to access the inside are under the manufacturers sticker on the underside. It was difficult to open up, and there was some shielding that was around the electrical connections that had to be gently removed and then reattached. It does have some vents on the bottom to help with cooling.
If you have comments or suggestions, Email me at firstname.lastname@example.org
Created with gnu emacs and template-toolkit, not some sissy HTML editor.
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