Hitachi Hard Drive Repair: A Tale of Two Drives

When Two Drives are Better Than One…

The client in this Hitachi hard drive repair case didn’t just have one hard drive in their computer. They also had an M.2 PCIe SSD connected to their motherboard as well. The SSD was more than just another storage device. It fulfilled a special function. Instead of just using it as extra space, the client could use it as a cache.
In your computer, a cache stores data so that you can quickly and easily bring it up again when you need it. Your CPU and GPU have their own dedicated memory to speed up their performance and reduce load. Your Internet browser also caches data, allowing you to load frequently-accessed web pages more quickly (and cut down on the bandwidth you use!).

With the explosion of solid-state memory, hard drive and computer manufacturers have tried a lot of tricks to combine hard disk drives with SSDs. Hard disk drives are cheap for their capacity, while high-capacity SSDs still cost an arm and a leg. When you want ample storage space and blazing fast speeds, what can you do?

…And When They’re Not

In this data recovery case, the client’s SSD was set up as a cache for their main HDD. The SSD stored some of the client’s most frequently-used files, as well as frequently-accessed program files and operating system files, so the computer could boot up and run programs more quickly.

When you use an SSD like a cache, you aren’t erasing any data from the hard drive; the SSD stores the most recent revisions to those files and writes them back to the hard drive to prevent any possibility of data loss at a later time. That way, if the SSD fails, the client shouldn’t lose any data. (Depending on how the cache is set up, though, the most recent revisions made to critical files might not make it back to the hard drive.)

However, when the HDD fails, that’s another story. The SSD is just a cache; it can’t do much on its own. Your computer still needs the HDD to boot from, even though the SSD takes care of a lot of the heavy lifting. And so, when this client’s Hitachi hard drive started making the dreaded “Click of Death”, it was time for them to call on some Hitachi data recovery specialists.

Hitachi Hard Drive Recovery Results

We’re no strangers to Hitachi HDD recovery. Once we’d fixed the myriad problems affecting the client’s failed Hitachi hard drive, our Hitachi hard drive repair experts could start imaging its contents. Due to the drive’s firmware loading issue, it needed its hand held by our engineers through the whole imaging process. After carefully guiding the hard drive, our engineers successfully imaged 41.5% of the sectors on the hard drive’s platters. The remaining sectors were either empty (not part of the drive’s used area) or destroyed (due to the severe platter damage).

With 41.5% of the binary successfully read, our engineers could recover 95.6% of the drive’s file definitions. We had 86% of the known files on the disk fully recovered, including several of the client’s several mission-critical Outlook PST files. However, several other Outlook files could only be partially recovered. There were gaps in these partially-complete files which had corrupted the files prevented them from working. However, our technicians successfully repaired the client’s PST files, saving their most critical data.

A few of the client’s other important files lived inside their healthy SanDisk SSD. While the SSD was very sparsely populated, some valuable data had made it onto the drive. Thanks to their use of the SSD as a cache, storing frequently-used files for fast access, the client had a handful of the most recent revisions of their most recently- and commonly-used files on the perfectly healthy SSD. Our engineers combined the recovered data from both the repaired Hitachi drive and the SanDisk SSD. The results were good; we had recovered the client’s most important data. We rated this Hitachi hard drive repair case a high 8 on our ten-point case rating scale.