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Fast reads on USB3 as advertised; otherwise unimpressive 10/22/2013
This review is from: SanDisk Ultra 32GB USB 3.0 Flash Drive Model SDCZ48-032G-A46
Decent USB3 read speeds; advertised 80 MB/s reads, measured 63.5 MB/s read.
USB2 read and write speeds not so hot
USB3 write speeds are quite dismal
First, the 32gb "Ultra" drive performs largely as SanDisk describes. They make no mention or promise or write speeds, only reads. I hope to provide clarity on what they don't say, and demonstrate how it works on older legacy USB2.0 ports.
Primarily I wanted this to transfer large burned DVD MKV files (typically 4-7 GB sizes on average). For that purpose, I can't recommend it. The following was a read/write test of a 3.25 GB MKV file on a fairly modern machine with an super fast SSD on the other end; freshly formatted flash drives using exFAT:
Measured speed on USB 3.0 port: Read 63.5 MB/s; Write 9.69 MB/s
Measured speed same PC, older USB 2.0 port: Read 31.1 MB/s, Write 8.25 MB/s
For reference, a much older PC with USB2 only ports measured an even less 6.35 MB/s write, 19.2 MB/s read with the SanDisk Ultra 32GB.
By comparison, a fairly high performing (for it's time) 8GB USB2 competitor from a few years back (brand named after "a person who virogously defends their country", the model is "angry"), copying the same files does the task (on a USB2 port) 26.6 MB/s read, 15.2 MB/s write.
All machines running WIndows 7 64 bit, all the latest driver and OS updates installed.
If your purpose is to write files on it >>in no big hurry<< through the course of a day, and pull them off rapidly all at once on another (USB3) machine, then this is probably a good choice for you. There's nothing wrong with it in that regard. It works as advertised, just won't knock your socks off.
But if you're like me and need to copy large files en masse to move elsewhere, well ... the write time is excruciating and has me looking longingly at my old USB2 flash drive. This isn't the best choice for that..
The "Extreme" series of this Sandisk brand promises faster write (and read) speeds, and is well reviewed. I'll return this and fork out the extra cash for one of those, or perhaps an SSD, instead. It's a great brand and highly recommend their media for camera gear, but with this I expected better.
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