SanDian Extreme PRO 1TB

• Obtained from: AliExpress
• Price paid: $6.62
• Advertised capacity: 1TB
• Logical capacity: 1,072,694,296,576 bytes
• Physical capacity: 29,943,033,344 bytes
• Fake/skimpy flash: Fake flash
• Protected area: 0 bytes
• Speed class markings: U3, V30, A2
• CID data:
  • Manufacturer ID: 0x00
  • OEM ID: 0x0000
  • Product name: 0x4150505344 (ASCII: APPSD)
  • Product revision: 0x00

Card #	1	2	3	Average
Manufacture date	Apr 2014	Apr 2014	Apr 2014	N/A
Serial number	0x12800006	0x12800007	0x12800000	N/A
Sequential read speed (MB/sec)	16.71	16.78	16.62	16.70
Sequential write speed (MB/sec)	15.33	14.33	10.27	13.31
Random read speed (IOPS/sec)	415.03	1,123.40	1,089.49	875.97
Random write speed (IOPS/sec)	9.94	0.43	0.42	3.60
Read/write cycles to first error	41	662	23	242
Read/write cycles to complete failure	1,283	783	Not yet determined	1,033
Total days to complete failure	98	80	Not yet determined	89
Card reader used	JJS CR-UTC4AC	JJS CR-UTC4AC	JJS CR-UTC4AC	N/A
Package front				N/A
Package back				N/A
Card front				N/A
Card back				N/A

Discussion

There’s not much to say about this card that is going to be different than the 128GB version. Like its smaller sibling, this card was disappointing at best.

Performance metrics were well below average and were only marginally better than the 128GB version — and, like the 128GB version, were not good enough to merit any of the performance marks that it carried.

Like many of the low-quality cards I’ve tested, sample #1 started experiencing errors after only a few read/write cycles, and the number of errors only increased as time went on. It was declared dead after 50% of its sectors had been flagged as bad. Here’s what the graph of this card’s progression looked like:

Sample #2’s first error was a data loss error during round 663. It continued to progressively degrade until it got to just shy of the 10% failure mark, at which point it stopped responding to commands. Here’s what the graph of this card’s progression looked like:

Sample #3’s first error was a 32-sector wide data loss error during round 24; it has survived 940 read/write cycles in total so far.

July 20, 2024 (current number of read/write cycles is updated automatically every hour)