What do the current, worst, and threshold SMART values mean

bad-sectorshard drivehard-drive-failuresmart

I have a 2TB internal hard drive that might be failing. It spends several minutes at 100% usage when I first turn it on since I installed Windows 10, and yesterday it reported a corrupted Recycle Bin.

I downloaded CrystalDiskInfo, and the pertinent information is reproduced below:
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In short, the Uncorrectable Sector Count count is 100, and this is a "caution"-level problem on the drive. No other labels are "caution".

I'm not sure what to make of the Current, Worst, and Threshold values. I know that some of their actual values vary by manufacturer, and I've also read that if a current value is below a threshold, that statistic has failed.

The value of the Uncorrectable Sector Count is 100, which is also its worst-recorded value, and the stat has a threshold of zero. Additionally, various other stats read that 100 is both their current and worst while not being marked "caution".

Why is Uncorrectable Sector Count being displayed as caution if various other stats with the same value and threshold aren't? How can a lower-than-threshold value occur with a zero threshold? Is this a sign of imminent drive failure or is the tool merely miscalibrated?

EDIT: Seagate's SeaTools utility has reported that SMART is OK, but it didn't say anything else.

Best Answer

Why is Uncorrectable Sector Count being displayed as caution?

You need to look at the raw value (8) in this case. There have been 8 events.

The raw value of this attribute indicates the total number of uncorrectable errors when reading/writing a sector.

In this particular case, I would keep an eye on the value and if it continues to increase then replace the drive:

This is a critical parameter. Degradation of this parameter may indicate imminent drive failure. Urgent data backup and hardware replacement is recommended.

S.M.A.R.T. Attribute: Uncorrectable Sector Count

Attribute ID: 198 (0xC6)

Hard drives, supporting this attribute

Samsung, Seagate, IBM (Hitachi), Fujitsu (not all models), Maxtor, Western Digital (not all models)

Description

Uncorrectable Sector Count S.M.A.R.T. parameter is a critical parameter and indicates the quantity of uncorrectable errors. The raw value of this attribute indicates the total number of uncorrectable errors when reading/writing a sector.

Recommendations

This is a critical parameter. Degradation of this parameter may indicate imminent drive failure. Urgent data backup and hardware replacement is recommended.

Source S.M.A.R.T. Attribute: Uncorrectable Sector Count

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