Check this out - from Hewlett Packard:
Bulletin: HPE SAS Solid State Drives - Critical Firmware Upgrade Required for Certain HPE SAS Solid State Drive Models to Prevent Drive Failure at 32,768 Hours of Operation
This HPD8 firmware is considered a critical fix and is required to address the issue detailed below. HPE strongly recommends immediate application of this critical fix. Neglecting to update to SSD Firmware Version HPD8 will result in drive failure and data loss at 32,768 hours of operation and require restoration of data from backup in non-fault tolerance, such as RAID 0 and in fault tolerance RAID mode if more drives fail than what is supported by the fault tolerance RAID mode logical drive. By disregarding this notification and not performing the recommended resolution, the customer accepts the risk of incurring future related errors.
Atomic Fungus runs the numbers:
32,768 is 2 to the 15th power. Exactly. And so what happened is, some register or counter or something hit 32,767, and when it tried to go to 32,768, BLAMMO.
If you look at it in binary it becomes more obvious what happened:
32,767 is 0111 1111 1111 1111. (Hex: 7F FF)
32,768 is 1000 0000 0000 0000. (Hex: 80 00)
The drive bricks when bit number 15--the most significant digit--goes from a 0 to a 1. I've got a fiver that says that someone used a signed variable when he should have used an unsigned one. Because when you're talking about signed binary numbers?
0111 1111 1111 1111= 32,767
1000 0000 0000 0000=-32,768
...and the software reads out those bits and says "Negative hours! Nope!" and crashes.
Classic PEBCAK error.
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