A: Answer In simple terms, these can be used in regular PCs, but you are paying for features that you will not use or not very helpful for regular PC user. In fact, one could argue that one of the features supported by these drives is actually (mildly) harmful to ordinary user. Now the long explanation. RED drives are meant to be used with RAID controllers. RAID controllers manage error recovery differently and therefore need disks to limit the time they spend recovering data from platters. Thus there drives will not try as hard as they could try to recover data when something goes wrong. This feature is called TLER (time limited error recovery) NAS drives have TLER supported and usually turned on by default. It may be possible to turn it off. However why would you pay for this and other features (like vibration tolerance/sensors etc) and not use them? Note that desktop drives usually do not have TLER and you should not put them in a RAID enclosure.

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