There are still many times when having a huge amount of storage at a low price is more important than having the speed of an SSD and the Western Digitial Black family of drives is perfect for those scenarios.  This 7200RPM HDD has five 800GB platters and a 64MB cache in the 4TB model TechARP reviewed though you can get smaller models if you so desire.  While the drive will not compete against and SSD you can see in the review that this drive tops the other platter based models performance by a noticeable margin.  If you need a large amount of space but can't pay around $1.00/GB then don't forget that HDDs are also still evolving.

"The new-generation Western Digital Black family differs from the previous generation by its use of Advanced Format Technology, which allows for greater capacity and throughput. The new Western Digital Black family now consists of five models, which differ only in their storage capacities."

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Storage