I purchased this
PNY 32 GB microSDHC Flash Memory Card (P-SDU32G10-EFS2) over one month ago, to expand the storage of my
Pandigital Planet 7" Android Tablet (R70A200). At that time, this 'class-10' card was priced just slightly above other 'class-4' cards, so it looked like a good deal. After thoroughly testing the card, however, I was disappointed by its lackluster performance.
I benchmarked this PNY card upon its arrival, using the "Flash Memory Toolkit v2.0". Its read speed is consistently high at 14-18MB/s. But its write speed is strongly dependent on the file size:
- For smaller files of 2-5MB, its write speed is very poor at just 3-5MB/s
- For larger files of 10-15MB, its write speed improves to about 8MB/s
(See the performance chart I uploaded to 'Customer Images' section for details)
Next, I tested the same card using "H2testw v1.4". This program measures the sequential read/write speed for 1GB files. Under this test, the PNY card achieved write speed of 9.5MB/s and read speed of 18MB/s.
I repeated the above tests on two different computers using two card readers, and obtained consistent results. Just for reference, I have previously benchmarked the
PNY Professional 16 GB Class 10 SDHC Card (P-SDHC16G10-EF) under identical conditions. It was able to achieve write speed of 13.6MB/s and read speed of 18.5MB/s. So the problem is not with my setup.
For a card to be marketed as 'Class-10', it must be able to deliver a MINIMUM write speed of 10MB/s. This PNY micro-SDHC card, however, can only achieve a MAXIMUM write speed of 9.5MB under best-case scenario. In other cases, such as when used in a digital camera (file size around 3-5MB), this so-called calss-10 card actually performs slower than a
SanDisk class 4 microSDHC SDSDQM-032G.
It appears to me that PNY has loosen its definition of 'class-10', in order to market this micro-SDHC card at a higher price. An even more disturbing observation is that: this practice seems to be a growing trend among memory card makers. Case in point:
- The
Kingston Digital 16 GB Class 10 SDHC Card SD10G2 performs much slower than Kingston 'class-4' card when used in a digital camera.
- The
SanDisk Ultra 16 GB 6 SDHC (SDSDRH-016G-A11) was called a 'class-4' one year ago. But now the same Ultra card is marketed as a 'class-6'. Although to be fair, the old Sandisk Ultra card actually performed better than most other brands of 'class-6' cards.
I despise deceptive marketing claims, therefore I cannot recommend this PNY 'class-10' micro-SDHC card.
[Update on Dec 2, 2011]
I double-checked the PNY card using another program (CrystalDiskMark v3.01). The result is actually worse than my previous finding. For sequential writing of huge files (500MB) it only reached 8.65MB/s. See my newly uploaded chart in 'Customer Images' section for details.