Counterfeit SD Cards.

I recently bought a number of SanDisk cards from Amazon and some from Amazon sellers. Several were counterfeit.

Here is an example. I bought Sandisk Ultra 8GB, 16GB, and 32GB. The 8GB is clearly counterfeit Here is it's CID and a performance test:

Manufacturer ID: 0X12
OEM ID: 4V
Product: MS
Version: 0.0
Manufacturing date: 5/2014

Type is FAT32
Card size: 7.99 GB
File size 5 MB
Buffer size 512 bytes
Starting write test, please wait.

write speed and latency
speed,max,min,avg
KB/Sec,usec,usec,usec
70.61,137276,2476,7242
70.77,136732,5280,7226
70.96,119376,5276,7206
71.02,119312,5216,7200
70.93,119272,5276,7210
71.03,119172,5216,7199
71.04,119156,5212,7198
71.04,119112,5216,7199
70.93,119152,5212,7209
71.03,119132,5212,7199
Starting read test, please wait.

read speed and latency
speed,max,min,avg
KB/Sec,usec,usec,usec
263.50,80812,1168,1937
264.59,2856,1168,1929
264.59,2856,1164,1929
264.60,2860,1168,1929
264.59,2860,1168,1929

The write speed, 71 KB/se,c and write latency,119 ms, are really poor. The CID is totally wrong.

Here is the 16 GB version of the card. I think it is genuine.

Manufacturer ID: 0X3
OEM ID: SD
Product: SL16G
Version: 8.0
Manufacturing date: 4/2014

Type is FAT32
Card size: 15.93 GB
File size 5 MB
Buffer size 512 bytes
Starting write test, please wait.

write speed and latency
speed,max,min,avg
KB/Sec,usec,usec,usec
243.48,20076,1740,2096
243.57,21888,1744,2096
243.96,21560,1740,2092
243.51,22836,1744,2096
243.84,21416,1744,2093
243.46,20164,1712,2096
243.64,20392,1744,2095
243.74,22168,1744,2094
243.90,20640,1744,2093
243.82,21536,1740,2093
Starting read test, please wait.

read speed and latency
speed,max,min,avg
KB/Sec,usec,usec,usec
496.94,2052,1004,1024
497.08,2056,1004,1024
497.04,2056,1004,1024
496.99,2056,1004,1024
497.04,2060,1004,1024

Seems OK. New cards don't do too well on SPI but 243 KB/sec is way better than 71 KB/sec and 20 ms compared to 119 ms for write latency.

Here is a 32 GB that seems to have a good CID but poor latency.

Manufacturer ID: 0X3
OEM ID: SD
Product: SL32G
Version: 8.0
Manufacturing date: 6/2014

Type is FAT32
Card size: 31.91 GB
File size 5 MB
Buffer size 512 bytes
Starting write test, please wait.

write speed and latency
speed,max,min,avg
KB/Sec,usec,usec,usec
243.57,78984,1624,2096
242.66,69304,1620,2103
245.36,77012,1612,2080
242.28,76568,1624,2107
246.34,98144,1620,2072
244.45,68888,1620,2088
241.52,100384,1616,2113
243.85,96224,1624,2093
243.36,74688,1620,2097
243.53,93152,1620,2096
Starting read test, please wait.

read speed and latency
speed,max,min,avg
KB/Sec,usec,usec,usec
480.83,2412,1044,1059
480.83,2416,1044,1059
480.83,2424,1044,1059
480.88,2416,1044,1059
480.88,2412,1044,1059

The long unstable write latency might mean it's not genuine. I don't have another 32 GB card. I have another 16 GB card and it has short write latency.

Kind of disgusting.

sd8gb.jpg

sd16gb.jpg

sd32gb.jpg