Hard Disk Drive Repair

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The Toshiba OCZ TL100 is an entry-level, budget-friendly SSD first announced in September. Toshiba is positioning the SSD as an HDD replacement and touting benefits one would expect from an SSD over HDD. This inculdes dramatic improvement in boot times and overall performance, with lower power consumption resulting in longer battery life. The TL100 uses Toshiba’s TLC NAND flash memory technology, and has one of the lowest suggested retail prices on the market for an SSD.

Toshiba is promoting the benefits of replacing an HDD with its new TL100 SSD instead of making claims against other value SSDs on the market. From a performance perspective, the company claims the TL100 can hit sequential reads up to 550MB/s and sequential writes up to 530MB/s. With random performance, the company is claiming the TL100 can hit 85K read and up to 80K IOPS write. The SSD comes in two capacities (120GB and 240GB) with total bytes written (TBW) of 30TB and 60TB, respectively.

The Toshiba OCZ TL100 SDD comes with a three-year warranty and starts for under $50 for the 120GB. Those who are interested can pick up the 240GB for about $68.

Toshiba OCZ TL100 SSD specifications

Capacities: 120GB, 240GB

NAND type: TLC

Interface: SATA 6Gb/s

Form factor: 2.5”, 7mm height

Performance

Sequential Read: Up to 550MB/s

Sequential Write: Up to 530MB/s

Random Read: Up to 85K IOPS

Random Write: Up to 80K IOPS

Endurance

TBW:

240GB capacity: 60TB

120GB capacity: 30TB

Environmental

Operating Temperature: 0°C to 70°C

Storage Temperature: -40°C to 85°C

Shock Resistance: 14.7 km/s^2 {1500 G} (0.5 ms)

Vibration: 196 m/s^2 {20 Grms} (Peak, 10 to 2,000 Hz)

Certifications: CE, BSMI, RCM, KCM, UL, RoHS + RoHS2

Physical

Dimensions: 100 mm x 69.85 mm x 7.00 mm

Weight: 37.5g

Warranty: 3-year

Design and build

The Toshiba OCZ TL100 is a 2.5” SSD with a 7mm z-height and an aluminum case. The front of the drive has a sticker with the Toshiba OCZ branding. The rear of the case has another sticker with more information about the drive, such as capacity and model number.

To open the drive up, one simply needs to pop the two parts of the case apart. The case is held together with tabs. On the top of the PCB, there are two NAND packs and a Toshiba controller.

On the bottom of the PCB board, one can see two more NAND packs.

Consumer Synthetic Benchmarks

All consumer SSD benchmarks are conducted with the StorageReview HP Z640 Workstation. We compared the OCZ TL100 to the following drives:

Samsung 850 EVO 1TB

Samsung 850 EVO 2TB

Crucial BX100 1TB

Crucial BX200 480GB

Crucial BX200 960GB

OCZ Trion 150 960GB

OCZ Trion 150 480GB

Samsung 750 EVO 250GB

All IOMeter figures are represented as binary figures for MB/s speeds.

Our first test measures 2MB sequential performance. The TL100 performed a little less than average with read speeds of 473.67MB/s, and though not terribly far behind the leaders, it did score near the bottom of the pack we tested. The drive did a bit better with a write speed of 440.38MB/s. With write, the drive performed slightly above median.

Moving to our 2MB random transfer performance, the TL100 showed similar placing, doing a bit better in placement with reads (414.12MB/s or sixth overall) and a bit lower with writes (304.77MB/s or fifth overall).

Switching to smaller 4K random transfers, the TL100 began to lag behind the other drives a bit farther. The TL100 gave us a read speed of 29.47MB/s and a write speed of 80.81MB/s. It wasn’t at the bottom of the pack in either score, but it was close.

When looking at 4K random throughput, the TL100 once again finds itself on the lower end of the scale with a write throughput of 20,687 IOPS and a read throughput of 7,545 IOPS.

When looking at 4K latency, the TL100 had an average latency a little on the high end (0.048ms) with only the BX200 480GB being higher. Max latency was also a tad high (72.13ms) but much lower than the BX200 drives that were over 100ms higher than the TL100.

Our next test shifts to a workload with 100% write activity that scales from 1QD to 64QD. In this scenario, the TL100 finished about in the middle of the pack, peaking at about 72K IOPS before settling around 63K IOPS.

Shifting focus to a 100% read activity, the TL100 gave a slightly better performance coming in fourth overall with around 84K IOPS.

Our final consumer-synthetic benchmarks compare the drives in a series of mixed-server workloads with a queue depth of 1 to 128. Each server profile has a strong bias towards read activity, ranging from 67% read with the database profile to 100% read in the web server profile.

The database profile features a 67% read and 33% write workload, focusing on transfers around 8K in size. Here, the TL100 settled in near the bottom of the pack, finishing off around 27K IOPS.

Our next benchmark is the read-only web-server profile, which uses transfer sizes ranging from 512 bytes to 512KB. In this scenario, the TL100 placed about the same as above, finishing around 18K IOPS.

During the file-server profile, which has 80% read and 20% write workload spread out over multiple transfer sizes ranging from 512-bytes to 64KB, the TL100 placed just above last with 15,380 IOPS to the 750 EVO’s 14,902 IOPS.

The last profile looks at workstation activity, with a 20% write and 80% read mixture using 8K transfers. Here the TL100 placed last by some margin. The drive started out and stayed last throughout the benchmark, finishing just under 19K.

Consumer Real-World Benchmarks

While the results of synthetic benchmarks are important in identifying the key strengths and weaknesses of a drive, performance in these tests does not always translate directly into real-world situations. To get a better idea how the Toshiba OCZ TL100 drive will handle itself in the field, we will chart StorageMark 2010 HTPC, Productivity, and Gaming traces against comparable drives. Higher IOPS and MB/s rates with lower latency times are preferred.

The first trace is based on use as a Home Theater PC (HTPC). The test includes playing one 720P HD movie in Media Player Classic, one 480P SD movie playing in VLC, three movies downloading simultaneously through iTunes, and one 1080i HDTV stream being recorded through Windows Media Center over a 15-minute period.

The TL100 scored 3,672 IOPS, 170.58MB/s, and had a latency of 2.151ms. In all three scores, the drive scored considerably poorer than the rest of the pack.

The next trace simulates disk activity in an office workstation or productivity scenario. This test includes three hours of operation in an office productivity environment with 32-bit Windows Vista running Outlook 2007 connected to an Exchange server, web browsing using Chrome and IE8, editing files within Office 2007, viewing PDFs in Adobe Reader, an hour of local music playback, and two hours of streaming music via Pandora.

With our productivity trace the TL100 results were not good. The drive scored 2,081 IOPS, 61.21MB/s, and a latency of 3.82ms. The next closest scores were twice as good in all three aspects.

The final consumer real-life benchmark simulates disk activity during gaming. This simulation taxes the drive’s read performance, with 6% write operations and 94% read operations. The test consists of a Windows 7 Ultimate 64-bit system pre-configured with Steam, and with Grand Theft Auto 4, Left 4 Dead 2, and Mass Effect 2 already downloaded and installed. The trace captures the heavy read activity of each game loading from the start, as well as textures as the game progresses.

In our gaming benchmark, the TL100 again came in last place across the board, though there wasn’t such a vast difference in placement as there was with the productivity trace. Here the TL100 scored 5,432 IOPS, 289.37MB/s, and a latency of 1.415ms.

Conclusion

The Toshiba OCZ TL100 is a value 2.5” SSD aimed pretty specifically at replacing HDDs. The drive comes in two capacities: 120GB and 240GB. Instead of marketing the drive against other value SSDs, Toshiba is highlighting the benefits of replacing an HDD with the TL100. The benefits are the usual suspects of faster boot times and overall performance, as well as lower power consumption and longer battery life for notebooks. An attractive feature of the drive is its MSRP of under $50 for the 120GB. This price makes the TL100 one of the cheaper SSDs on the market based on retail price.

With performance, we compared the TL100 to several other value SSDs. The drive did not perform so great against the other value drives, which are generally quite a bit slower than performance models already. While the performance wasn’t great in just about all of our tests, as stated by the company, users would see a fairly big boost against their existing HDDs. In our sequential 2MB IOMeter, the TL100 was able to hit 473.67MB/s read and 440.38MB/s write. In our random 2MB IOMeter, the TL100 was able to hit 414.12MB/s read and 304.77MB/s write. With our 4k tests, the TL100 dropped down in placement against the other drives even more. The TL100 struggled through the 4k benchmarks, floating around the middle to bottom. In our mixed-server workloads, the TL100 stayed near or at bottom.

While the above performance wasn’t terrific, the TL100 really fell on its face in our consumer real-world benchmarks. In all three tests the drive was at the bottom of the pack, and in our productivity trace, it was last by a wide margin. Scores were uncomfortably low to the point where we had to cross reference them against our past HDD and SSHD results to verify it was still faster. Again, we want to note that the drive is a cost-effective, HDD replacement that makes no real performance claims against other SSDs. With that said, outside of an incredible doorbuster sale, it doesn't take much (about $5-15) to upgrade to a competing drive that offers substantially stronger real-world performance.

Pros

Very low price

Cons

Very low performance compared to other SSDs

Poor consumer real-world performance

The Bottom Line

The Toshiba OCZ TL100 is a low-cost HDD replacement, though may not be the best choice for those looking for a big performance boost.

Read Main Article: http://www.storagereview.com/toshiba_ocz_tl100_ssd_review

Related article: Solid-State Drive Best Practices On Mac OS

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How to repair a dead hard drive

Recover your hard drive: it's easier and cheaper than you think

When a hard drive goes bad, the first thing you'll probably do is have a good old curse at the platter gods for picking on you. You then might decide to have a bit of a panic when you realise that you didn't back up your files.

Shortly after sweating out a few pounds, you'll probably have a go at fixing it. Well, it's worth a shot after all. But chances are, unless you know exactly what the problem is and have the skills necessary to fix it, you're pretty much up poop alley.

If you're lucky and the disk head or motor hasn't been damaged, the problem could lie in the controller board or printed circuit board (PCB). Often, when there's a power surge or the drive overheats, it can damage the board. If this happens, then you can quite easily replace the PCB with one that is working and bring your hard drive back to life.

A common sign that a PCB has been in the wars is a scorch mark, but sometimes there are no visual cues to give the game away.

First things first

The PCB might not be the problem after all, then, but it's the one area of the drive that you should tackle first when something goes wrong. After all, a replacement PCB from a specialist like www.hdd-parts.com will set you back around £25 delivered to your door, so it's a relatively inexpensive way of fixing your drive.

If you were feeling plucky, you could just go to a data specialist and get a man in a white coat in a lab to carefully take your entire hard drive apart and put it all back together, in the hope of rescuing your drive, but you'll be looking at a bill for at least £1,000. Unless you really, really need the files on that drive, you'll avoid this route and go down the PCB road first.

Back to life

Does it really work? Well, we tried it on a drive that had suddenly stopped working one day. There were no horrible clicking sounds, it simply wouldn't power on – the thing was lifeless. So, we replaced the PCB with an identical working one and managed to get it working again.

This wasn't after trying it on many different drives – this was the first one we'd worked on, so it wasn't a fluke.

It's worth mentioning that if this works for you, and there's a pretty good chance that it will, once it's up and running again, don't get lazy and put it back in your PC. If it failed once, there's a probability that it will fail again. Our advice is to transfer all your sacred files to another drive and then bin it… or pop it in the trophy cabinet.

1. Take drive details down

Get a replacement PCB identical to your current one, otherwise it won't work. Note down the model number (below the S/N), the P/N, the Firmware code, Date code and Site code, as well as the Main Controller IC number, which is located on the main square black chip in the middle of the actual PCB. In our case it was the six-digit code near the top, above the word 'SEAGATE'.

2. Search for it online

Go to hdd-parts website and enter the model of the dead drive (in our case, it's the 11-digit code two lines down from the top of the drive) into the search box at the top of the page. This won't give you the exact model, but look through the list of results and find the drive that matches all the numbers you noted down in the first step. Now, buy it!

3. Check your parts

The new PCB should take about six to 10 working days to arrive through the post. When the mail man comes round, you should receive a box with a replacement working PCB inside, as well as a torx screwdriver and installation instructions – not that you'll need this last bit. If something is amiss, email the company and they will get back to you within a couple of days.

4. Remove the old PCB

On top of the PCB you'll see five screws connecting it to the hard drive. Undo them using the torx screwdriver included in the kit, making sure that you don't lose any of them. They're pretty tiny, so once you've managed to remove them all, place them into a zip-lock bag so they don't go astray if you decide to have a break between now and the next step.

5. Attach new PCB

Make sure you ground yourself – an easy way of doing this is to put on an anti-static wrist band – and then carefully take the replacement PCB out of its anti-static bag. Pop it onto your old hard drive, making sure you line it up with the original screw holes. Take the screws from your zip-lock bag and screw the PCB down, ensuring each screw is reasonably tight.

6. Try out your drive

Turn on your PC. Then connect your hard drive to your dock, plug it into the PC and power it up. If the problem with your old drive was due to a faulty PCB, replacing it should now allow your drive to be recognised properly. Access the fi les you need, then copy them to your PC. Don't attempt to use the drive once this is done: chances are it might turn faulty in the future.

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Beneath the Board

Underneath the board area unit the connections for the motor that spins the platters, also as a highly-filtered vent hole that lets internal and external air pressures equalize:

Removing the cover from the drive reveals an extremely easy however very precise interior:

In this picture you'll be able to see:

The platters - These generally spin at 3,600 or 7,200 rpm once the drive is operating. These platters area unit manufactured to wonderful tolerances and area unit mirror-smooth (as you'll be able to see during this fascinating self-portrait of the author... no easy thanks to avoid that!).

The arm - this is still the read/write heads and is controlled by the mechanism within the upper-left corner. The arm is ready to maneuver the heads from the hub to the sting of the drive. The arm and its movement mechanism are extraordinarily light and quick. The arm on a typical hard-disk drive will move from hub to edge and back up to 50 times per second -- it's an incredible factor to watch!

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Electronics Board

The best thanks to perceive however a hard disk works is to require a glance within. (Note that gap a hard DISK RUINS IT, thus this can be not one thing to undertake reception unless you've got a defunct drive.)

Here could be a typical hard-disk drive:

It is a sealed aluminum box with controller electronics attached to at least one side. The physical science control the read/write mechanism and also the motor that spins the platters. The electronics additionally assemble the magnetic domains on the drive into bytes (reading) and turn bytes into magnetic domains (writing). The electronics square measure all contained on a tiny low board that detaches from the remainder of the drive.

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Capacity and Performance

A typical desktop machine will have a hard disk with a capacity of between 10 and 40 gigabytes. data is stored onto the disk within the kind of files. A file is solely a named assortment of bytes. The bytes can be the ASCII codes for the characters of a text file, or they could be the instructions of a software application for the pc to execute, or they might be the records of a data base, or they might be the pixel colors for a GIF image. in spite of what it contains, however, a file is solely a string of bytes. once a program running on the computer requests a file, the hard disk retrieves its bytes and sends them to the cpu one at a time.

There are 2 ways that to measure the performance of a hard disk:

Data rate - The data rate is the number of bytes per second that the drive can deliver to the CPU. Rates between 5 and 40 megabytes per second are common.

Seek time - The seek time is the amount of time between when the CPU requests a file and when the first byte of the file is sent to the CPU. Times between 10 and 20 milliseconds are common.

The other necessary parameter is that the capacity of the drive, that is that the range of bytes it will hold.

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Cassette Tape vs. Hard Disk

Let's check up on the large variations between cassette tapes and laborious disks:

The magnetic recording material on a cassette tape is coated onto a thin plastic strip. in a very hard disk, the magnetic recording material is layered onto a high-precision aluminum or glass disk. The hard-disk platter is then polished to mirror-type smoothness.

With a tape, you have got to fast-forward or reverse to induce to any specific purpose on the tape. this may take many minutes with a long tape. On a hard disk, you'll move to any purpose on the surface of the disk nearly instantly. In a cassette-tape deck, the read/write head touches the tape directly. in a hard disk, the read/write head "flies" over the disk, never really touching it. The tape in a very cassette-tape deck moves over the head at about 2 inches (about 5.08 cm) per second. A hard-disk platter will spin beneath its head at speeds up to 3,000 inches per second (about 170 mph or 272 kph)! The information on a hard disk is stored in extremely small magnetic domains compared to a cassette tape's. the size of those domains is made possible by the preciseness of the platter and therefore the speed of the medium. Because of these variations, a modern hard disk {is able|is in a very position|is ready} to store an incredible quantity of information in a small space. a hard disk also can access any of its info in a very fraction of a second.

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Hard Disk History

Hard disks were invented within the 1950s. They started as giant disks up to 20 inches in diameter holding simply some megabytes. They were originally known as "fixed disks" or "Winchesters" (a code name used for a well-liked IBM product). They later became called "hard disks" to distinguish them from "floppy disks." hard disks have a hard platter that holds the storage medium, as critical the flexible plastic film found in tapes and floppies.

At the simplest level, a hard disk isn't that totally different from a cassette tape. each hard disks and cassette tapes use an equivalent magnetic recording techniques described in however Tape Recorders Work. hard disks and cassette tapes additionally share the most important benefits of magnetic storage -- the magnetic medium is simply erased and rewritten, and it'll "remember" the magnetic flux patterns stored onto the medium for several years.

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Hard Drive Circuit Board Replacement Guide

How To Swap HDD PCB

Replacing a defective hard drive circuit card isn't a simple swap. The new PCB should be custom-made for your hard drive. while not the required steps to adapt to the new circuit board, your drive won't operate properly and data won't be accessible.

There area unit few things to grasp before you proceed:

1. Not each hard drive failure is because of a bad PCB—only about 25-30% of data loss happens because of failing electronic components. Even what looks to be a visible sign of a PCB failure might be a very completely different (often mechanical) issue. If time and data are important, contemplate sending us your hard drive for our diagnostics and PCB adaptation services.

2. when a circuit board fails, you will ought to take a couple of extra steps to create positive your hard drive is functioning with the new PCB. read this whole HDD circuit board Replacement Guide below to know the process, and improve your possibilities of successful data retrieval.

Step 1. Understanding PCB firmware

Most hard drive circuit boards possess rom, NV-RAM, or a controller chip that holds unique data needed to access the hard drive system area. we tend to decision this data “PCB firmware”. If PCB firmware is missing or incorrect, there's no access to the hard drive, and no access to user data. because of this, a straightforward circuit board swap won't build a faulty hard drive operational. it should be necessary to transfer the PCB firmware onto a replacement PCB.

In several cases, the rom or NV-RAM chip is external, and might be physically transferred (soldered) onto a replacement circuit board. The PCB replacement guide explains the way to try this yourself. typically the PCB firmware is found on the controller chip, and while not knowledgeable BGA make over Station, it's not possible to maneuver that chip onto a replacement PCB. that very same controller chip is commonly the matter within the original PCB. In these cases, a replacement chip should be reprogrammed with the proper PCB firmware (which Donor Drives will generate) with access to the first failed hard drive.

Step 2. hard drive diagnostics

There area unit typically several complications when an influence surge, together with a burned pre-amplifier, that is taken into account to be a mechanical failure associated with head disk assembly

1. Check the hard drive cables. we always recommend using a toaster-like external enclosure for testing purposes. it's terribly straightforward to work with, and permits easy accessibility to the hard drive whereas it operates, improving your ability to properly diagnose hard drive behavior.

2. will your hard drive spin? attempt to listen, touch it, or carefully lift it. If it makes a buzzing sound or a sound am passionate about it is attempting to spin, the failure is presumably a spindle seizure and has nothing to try and do with the circuit board. If you hear a tick, or don't hear or feel any movement, the PCB is perhaps defective.

3. If the hard drive spins, attempt to decipher if it makes a quiet ticking or clicking sound. will it spin for a minute and so slow down? Such behavior indicates a head crash, and is never a PCB problem.

4. For a commonly functioning hard drive that's not recognized by your computer, the difficulty can be something, as well as circuit board failure, bad sectors, firmware, or any mechanical issue. confirm if the hard drive is recognized by BIOS with correct parameters. If it is, then it's in all probability a firmware or logical hard drive failure, not a circuit board defect.

5. Proceed with Donor Drives circuit board Swap Guide if you think the PCB is faulty.

Step 3. Finding Replacement PCB

Finding an identical PCB for your hard drive are often difficult if the failing hard drive is rare; but, most of our customers will realize a match by following our Donor PCB Matching Article.

Step 4. Brand-Specific Replacement

Western Digital

WD has 2 types of PCBs.

Type 1 has an 8-legged U12 rom chip that must be swapped. See Step 4 of this card Replacement Guide.

Type two features a missing U12 chip, and PCB firmware is stored within the big “M” marvell Controller Chip. That chip can be transferred by a professional with a BGA work Station, or reprogrammed by Donor Drives.

Seagate

These hard drives have 2 architectures: barracuda (older) and F3 (new generation).

Barracuda architecture. These hard drives have a dot (.) within the firmware version (“3.CDA”, “8.01”, “3.03”, etc.). Most PCB swaps area unit easy (~85%). in the other 15 august 1945, a rom chip should be swapped.

F3 architecture. hard drives don't have any dot (.) within the firmware version (“CC44”, “0005HPM1”, “SD01”, etc.). The 8-legged firmware chip can have variety starting with 25, and should be transferred to a brand new circuit board. See Step 4 of this circuit board Replacement Guide.

Note: If your hard drive has a new PCB recognized by incorrect parameters (such as wrong model, different sn, or incorrect firmware), a computer electronics skilled or Donor Drives, LLC should swap the chip.

Toshiba

Most Toshiba boards have an 8-legged firmware chip that must be swapped. The chip will have a number starting with 25. See Step 4 of this Circuit Board Replacement Guide.

For some Toshiba families, the chip might be missing unique adaptive data stored in the large controller chip. That chip can be transferred by a professional with a BGA Rework Station, or reprogrammed by Donor Drives.

Hitachi and IBM

All Hitachi and IBM circuit boards have an 8-legged firmware chip that has a number starting with 25. See Step 4 of this Circuit Board Replacement Guide.

Maxtor

Adaptation service not required. A simple PCB replacement should work.

Samsung

Most of the time there is no need for adaptation service, but in some cases an 8-legged firmware chip (with a number starting with 25) must be transferred. See Step 4 of this Circuit Board Replacement Guide.

Fujitsu

PCB adaptation is not required, but occasionally, a firmware chip transfer is required. See Step 4 of this Circuit Board Replacement Guide.

Step 4. Example of PCB Replacement

Make sure the PCB Replacement is relative which PCB firmware must be transferred. read our guide carefully for instructions.

Examine your hard drive circuit board to examine if a rom chip exists. The rom is sometimes an 8-pin chip (4-pins on two sides) marked as U12 on Western Digital, or U6 or U5 on Hitachi. there's sometimes just one 8-pin chip on a hard drive circuit board. you may doubtless find a number starting with 25 on the chip. Western Digital USB-powered PCBs and a few newer, large-capacity Hitachi hard drives have 2 rom chips, therefore feel free to swap each.

If you are not certain that chip to swap, contact us, and that we can gladly help. For Western Digital PCBs, realize a U12 white marking on the chip side of the circuit board. A missing chip in place of U12 would indicate that the PCB firmware is embedded within the controller chip. That chip may be transferred by knowledgeable with a BGA rework Station, or reprogrammed by Donor Drives.

Once the chip has been located, perform the PCB chip swap. If you are doing not feel comfortable doing it yourself, send it to us for PCB Adaptation Service, or contact a neighborhood skilled. don't trust this task to a stranger—this chip is important for data access. an overheating rom chip may result in significant damage and information loss.

if you've got soldering expertise and therefore the required tools, you'll be able to try this at your own risk. the required tools are: a hot air station or heat gun, metal tweezers, grip tool, and an optional soldering flux. Begin by robust the new board to a table with the chip prepared. you'll be able to apply little bits of soldering flux on all 8 pins of the chip if you want. turn the heat gun or air station to high temperature and airflow settings. With one hand, hold the air-generating end a half-inch faraway from the chip for 10-15 seconds, whereas the opposite hand has the tweezers able to take away the chip. remove heat simply a bit from the chip, and take a look at to lift it with the tweezers. don't tear the rom chip from the PCB—it ought to return off with no force. Repeat this with the original rom chip. check that to recollect that aspect of the chip was on the board. there's a dot on each chips and PCBs just in case you forget that aspect was on the board. Next, align the fixed storage chip from the old board on the new board. Apply heat for 10-12 seconds, remove heat, and cool the board. check that that the rom chip sits tightly in situ. currently you'll be able to try plugging in your hard drive. If hard drive still does not spin: 1. There might be a different issue, such as a seized spindle. 2. For some modern WD drives, there could be a failed HDA preamplifier. 3. You haven’t fully soldered the chip. Check that all legs have a good connection to the PCB. 4. The chip was soldered on the wrong side. 5. The chip was damaged while soldering.

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How Hard Disks Work

Nearly every desktop computer and server in use today contains one or more hard-disk drives. Every mainframe and supercomputer is normally connected to hundreds of them. You can even find VCR-type devices and camcorders that use hard disks instead of tape. These billions of hard disks do one thing well -- they store changing digital information in a relatively permanent form. They give computers the ability to remember things when the power goes out.