This is the latest installment of my microSDHC craziness – the long-awaited Sandisk Ultra 32Gb UHS-I microSDHC. If anything, the Sandisk Ultra is pretty much the “yardstick” by which other cards are judged by – performance, value, compatibility and reliability all referenced to what Sandisk does. It has been the “no-brain” choice and recommendation for many years, although the wave of counterfeit cards had put a little dent in their reputation.
This card was purchased from an online auction seller, and appears to be a genuine product. The price was approximately AU$26.60, a hair cheaper than the Samsung Plus at AU$27.00. This package is mobile-themed, and includes a microSD to SD adapter. It claims “up to 30Mb/s”, which is presumably for read. There is also a free Android application available, although it’s not really of interest to me.
It claims to have a lifetime warranty, and is Made in China. There are many qualifying conditions and fine print on the rear. Careful reading of the “twice the speed” and “ordinary cards up to 5Mb/s write speed” implies this card is “exactly” Class 10.
There are no other inclusions aside from the card and the adapter. The card has unique print colouration compared to other vendors.
The printing on this card looks like a fairly low-quality error-diffusion dithered print. Not nice. But it does seem genuine.
The card’s details are as follows:
Size: 31,914,983,424 bytes CID: 03534453553332478000e4b46c00e123 CSD: 400e00325b590000edc87f800a4040c3
The size of the card is 452.5MiB larger than the Samsung Plus, but is 170.5MiB smaller than the Samsung Pro. It’s just below 32 “weasel” gigabytes, but is considered generous nowadays.
The card was filled with random data and verified three times with no problems as expected.
HDTune Pro with Transcend RDF8
The read speed averages 41.7Mb/s on HDTune with the Transcend RDF8, exceeding the claimed 30Mb/s.
HDTune Pro with Kogan RTS5301
A slightly higher read speed of 44.1Mb/s was achieved with the RTS5301, with no compatibility problem or workaround required. The card initialized in UHS-I mode every time. Compatibility is a strong point with the Sandisk card.
CrystalDiskMark with Transcend RDF8
The result from CrystalDiskMark implies that the card’s write performance with small blocks seems to be rather poor, and its sequential write lags behind other UHS-I cards in this class and price bracket. The Samsung Plus almost doubles the performance on the write column.
CrystalDiskMark with Kogan RTS5301
Similar performance was recorded with the RTS5301 reader. Nothing particularly special really. The performance is actually fairly similar to the Sandisk Ultra 64Gb UHS-I SDXC card.
H2testw with Transcend RDF8
The card completed the H2testw test without errors indicating the flash capacity is genuine. The write speed over the whole device was almost exactly 10Mb/s, the read speed was almost exactly 40Mb/s (which was above the 30Mb/s claimed by the packet). It is still pretty “average” as UHS-I cards are concerned.
I’m not sure if the card is artificially write-speed limited, but its write speed is pretty much exactly 10MB/s. As a result, it is easily out-performed by most UHS-I capable microSD cards at this capacity at sequential performance – in fact, the Samsung Plus, Samsung Pro and Sony High Speed cards are all twice as fast at writes and at least as good on read.
Price wise, the Samsung Plus is pretty much the same price, but twice as fast at write. It also has much better small block performance, and it’s backed by a major flash supplier, so I find it hard to recommend the Sandisk Ultra if the Samsung Plus is available. I suppose the Sandisk Ultra is easily obtainable, and its performance and compatibility is still very much “solid” …