Lexar Blue 633x 32GB

  • Obtained from: AliExpress
  • Price paid: $1.99
  • Advertised capacity: 32GB
  • Logical capacity: 31,719,424,000 bytes
  • Physical capacity: 31,719,424,000 bytes
  • Fake/skimpy flash: Skimpy (0.88% skimp)
  • Protected area: 83,886,080 bytes
  • Adjusted skimp: 0.61%
  • Speed class markings: Class 10*, U1, V10, A1
  • CID data:
    • Manufacturer ID: 0xad
    • OEM ID: 0x4c53 (ASCII: LS)
    • Product name: 0x4c58333247 (ASCII: LX32G)
    • Product revision: 0x10
Sample #123Average
Serial number0x3a0097a20x41b403fd0x41af03f6N/A
Manufacture dateAug 2023Aug 2023Aug 2023N/A
Sequential read speed (MB/sec)89.8990.4990.1090.16
Sequential write speed (MB/sec)28.6628.3027.9228.29
Random read speed (IOPS/sec)2,446.172,411.092,475.372,444.21
Random write speed (IOPS/sec)698.86668.24677.34681.48
Read/write cycles to first error1572672,057827
Read/write cycles to complete failureNot yet determinedNot yet determinedNot yet determinedNot yet determined
Total days to complete failureNot yet determinedNot yet determinedNot yet determinedNot yet determined
Package frontN/A
Package backN/A
Card frontN/A
Card backN/A


By mid-January 2024, I had started endurance testing on two of the Lexar Professional 1000x 64GB cards, and it became obvious that these cards had a pretty significant data integrity issue (see the discussion on those cards for more info). However, seeing as those were the only Lexar cards in my collection, I thought that it would be a pretty poor representation of Lexar as a whole — so I decided it would be good to include another Lexar model.

There’s one particular data point that strikes me as odd: the manufacturer ID. None of the sources I looked at listed manufacturer ID 0xad as belonging to Lexar — or anyone at all. This manufacturer ID is shared by two other brands in my collection: Chuxia and OV. In fact, all three not only had the same manufacturer ID, but also the same OEM ID. This could be a sign that these cards were fake; however, I didn’t see any other signs indicating that the card is fake — capacity is as advertised, and printing (on both the card and the packaging) was clear and high quality. The markings on the back of the card appear to have been printed on — as opposed the Lexar Professional 1000x 64GB, where it appears the markings were laser-etched — but this is about the only inconsistency I could spot off the bat. If this is a fake, it’s a pretty convincing fake.

However, I think there’s a more mundane explanation. The Lexar Professional 1000x 64GB cards have manufacture dates of Jan 2017 and Feb 2017, while these cards have a manufacture date of Aug 2023. Lexar was owned by Micron up until August of 2017, when they made the decision to sell the Lexar brand name to Shenzhen Longsys Electronics Co. — meaning that the two Lexar Professional 1000x 64GB cards would have been made by Micron, and these two would have been made by Longsys. Given that, I think manufacturer ID 0xad is probably assigned to Longsys.

Performance-wise, these cards did above average in all categories except sequential write speeds, which were slightly below average. The worst of the sequential write scores put this card in the 50th percentile for this category. However, random write speeds — a category which a lot of cards struggled with — were more than one standard deviation above average, with the worst of the three scores putting it in the 84th percentile. These cards easily surpassed the thresholds for all of the speed class marks that they bore. Honestly — not bad for a card that was only $1.99.

All three samples are still undergoing endurance testing:

  • Sample #1’s first error was an address decoding error during round 158; it has survived 4,092 read/write cycles so far.
  • Sample #2’s first error was an address decoding error during round 268; it has survived 2,790 read/write cycles so far.
  • Sample #3 was the only one of the three that managed to survive for at least 2,000 read/write cycles before experiencing its first error, which was — you guessed it — an address decoding error during round 2,058. It has survived 3,149 read/write cycles so far.

June 9, 2024

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