Flash Drives and Controllers: USB 3.0 vs. USB 2.0

The today’s most popular way of moving data around and transferring it from one computer system to another is definitely USB flash drives. However, now that we have gigabytes of data the USB 2.0 speed may become a bottleneck. Will the transition to faster USB 3.0 interface help flash drives resolve this issue and is it justified at this time?

by Dmitry Vasiliev
08/15/2011 | 08:39 AM

Although USB 3.0 is getting more and more popular, even the latest generation of mainboards do not always come with an appropriate controller. Chipsets are yet only expected to provide USB 3.0 support. As for the numerous PCs built out of older components, the good old USB 2.0 is still prevalent in that realm.

 

Of course, the newer standard will eventually replace the veteran (USB 2.0 has been in the ranks for a decade, which is only comparable to the PCI bus and PS/2 connectors which are already missing on some modern mainboards) but is there any point of keeping in touch with the progress and switching your peripherals to USB 3.0? Are USB 2.0 and 3.0 devices and controllers as compatible as they are declared to be? Is there any difference in performance between USB 2.0 and 3.0 disks when connected to a USB 2.0 controller?

We are going to answer these two questions in this review by comparing two USB 3.0 disks and a couple of USB 2.0 flash drives. The tests will be run on a Gigabyte GA-Z68X-UD3P-B3 mainboard which offers USB 2.0 ports (based on the Intel Z68 chipset) as well as USB 3.0 ones (based on an EtronTech controller).

Testing Participants

For this test session we took two USB 3.0 flash drives we had at hand. They came from Kingston and Kingmax. And we compared them to two USB 2.0 devices from the extreme ends of the product range: a cheap and slow ADATA and a fast, expensive and durable Corsair Survivor GTR.

We will now offer you a brief description of each product. The alphabetic order of their presentation is also coincidentally the order of increasing performance according to the official specs.

ADATA C905

This is a regular cheap USB flash drive (about $50 for 32 gigabytes) that can only be distinguished from others by its cute matte aluminum case.

The C905 is handy enough with its compact size, tight cap and low heat dissipation but even its specified specs (which are somewhat higher than what you can get from it in practical applications) do not promise any speed records. You’ve got to be patient if you own this drive.

Corsair Survivor GTR

The second disk we are going to test boasts excellent durability in the first place. The aluminum alloy casing with threaded joints and rubber gaskets can keep the device safe at a shock up to 1500 G. The Survivor GTR can be submersed into water by up to 200 meters and doesn’t fear vibrations, either.

The specified speeds are rather impressive (compared to average USB 2.0 products) and the device doesn’t get very hot at work. So, this is a top-end product which is reflected in its price. It costs more than most other 32GB drives, including USB 3.0 ones.

The Survivor GTR is large. It is the longest in this test whereas the diameter of its protective casing is comparable to that of the plump USB 3.0 drive from Kingston.

Kingmax ED-01

As opposed to many other USB 3.0 flash drives, this one is quite pocket-size. It has an ordinary square case made from black plastic. The silvery details are also plastic but with a metallized coating. The drive doesn’t get very hot at work, so you shouldn’t worry about overheat. The protective cap can be put on the drive’s back end by simply turning around by 180 degrees.

Kingston DataTraveler Ultimate 3.0

This is a heavy drive in a plump case with aluminum inserts and a blue activity indicator. It is comparable to the Corsair Survivor GTR in dimensions but, unlike the latter, does not feature any special protection.

The DataTraveler Ultimate 3.0 would get very hot during our tests. Its temperature was as high as 50°C, making it uncomfortable to touch the drive with your fingers. This may also have a negative effect on its service life.

This drive comes with a power cable that can help power it up when connected to USB 2.0 ports which provide a lower current (500 mA) compared to USB 3.0 (900 mA). So, you connect one end of the cable to the flash drive and the other two, to the computer’s USB 2.0 ports. We must confess we didn’t find this cable to be necessary. The drive was powered normally by any single USB 2.0 port of our testbed. There was no difference in terms of performance or temperature, either.

Testbed and Methods

Our testbed was configured as follows:

We installed the latest drivers from the manufacturers of our components. The tested disks were NTFS-formatted with the default cluster size.

The tested USB drives were connected to the mainboard’s USB 2.0 (Intel Z68) and USB 3.0 (EtronTech EJ168A) ports.

We used the following benchmarking tools:

There were three FC-Test patterns corresponding to three typical usage scenarios:

We also used CrystalDiskMark for you to be able to compare your results with ours if you want. We ran each test of that benchmark five times using 1000 megabytes of test data.

Performance in CrystalDiskMark

Let’s start with CrystalDiskMark. There are two screenshots for each drive. The first one refers to USB 2.0 connection and the second one, to USB 3.0.

ADATA C905

 

It’s easy to note that this old and rather slow USB 2.0 drive improves its read speed (by an average 10%) when connected to the USB 3.0 controller but its write speed remains roughly the same. This is rather unexpected. We thought the USB 2.0 interface had already been polished off so well that there would be no such difference between the controllers.

Corsair Survivor GTR

 

The Corsair is quite fast for a USB 2.0 flash drive and enjoys a performance boost when connected to the USB 3.0 controller. Its sequential read speed and its speed of reading 512KB data blocks improve by about 20%, and it reads small files twice faster than with USB 2.0! Like with the ADATA drive, its write performance doesn’t change much except that its sequential write speed grows by 10% on the USB 3.0 controller.

Kingmax ED-01

 

Being a native USB 3.0 drive, the ED-01 works much faster on USB 3.0 than on USB 2.0. However, we can see it having problems with writing: the native mode is faster than the legacy one at sequential writing only. The drive has a very low speed of writing 512KB data blocks even compared to its own performance in the same test with the USB 2.0 controller.

Kingston DataTraveler Ultimate 3.0

 

The second USB 3.0 drive is slower than the first one in terms of read speed when connected via USB 2.0 but leaves the competitor behind with USB 3.0. It also proves to be much faster than the rest of the tested drives in terms of writing, especially small files.

 

Performance in FC-Test

Now let’s see what we have in FC-Test. For each test we’ve got two tables (reading and writing) that show the performance of the drives with USB 2.0 and 3.0.

It’s easy to note that the drives are similar when reading a single 900MB file over USB 2.0. The only exception is the cheap and slow ADATA, yet even its performance is far from a total failure.

Every drive speeds up on the EtronTech controller but to a different degree. The ADATA is rather indifferent about the interface, the Corsair adds just a little to its USB 2.0 speed, but the two drives with native USB 3.0 double their performance.

When writing the same file, the drives differ even on the USB 2.0 controller. The Kingston falls behind in the leading trio whereas the low-end ADATA is much slower than its opponents.

When we switch to the USB 3.0 controller, the Kingston goes ahead and is followed by the other native USB 3.0 drive. Next goes the fast USB 2.0 drive from Corsair whereas the ADATA is hopelessly slow.

When reading medium-sized files of the MP3 pattern, the tested drives have almost the same standings on the USB 2.0 controller as in the previous test. The Kingston is somewhat slower than the Corsair and Kingmax whereas the ADATA is the slowest of all.

The standings are exactly the same as in the previous test when the drives are connected to the USB 3.0 controller.

We’ve got a different picture at writing, though.

First of all, we can see that the Kingmax fails this test irrespective of the USB controller. It’s even slower than the cheap ADATA with the USB 2.0 controller and cannot leave it behind on the USB 3.0 interface. These two drives are much slower than the Corsair and Kingston.

We should also note the Corsair’s excellent USB 2.0 performance and the superb results of the Kingston in USB 3.0 mode.

The ADATA drive shows a decent result when reading a folder with Microsoft Office 2007 (a lot of small files with but a few large ones: 3384 files with a total size of 450 megabytes). It beats the Kingston in USB 2.0 mode. The Corsair and Kingmax are ahead with similar results.

When connected to the USB 3.0 controller, the Kingmax is in the lead, followed by the Kingston. The Corsair accelerates on the USB 3.0 controller but cannot catch up with the native USB 3.0 products.

Writing a large number of small files is the most difficult test for flash memory. We’ve got two pairs of leaders and losers here. The ADATA and Kingmax are slow and cannot deliver 1 MB/s even. The Kingston and Corsair are in the lead, the Kingston enjoying a considerable advantage over its opponent.

Conclusion

As we have found out, there is indeed excellent compatibility between USB 2.0 and 3.0 devices and controllers. USB 3.0 drives are often faster when connected via USB 2.0 than native USB 2.0 products. The unpleasant exception was the Kingmax drive which had a poor speed of writing medium and small files, but its performance wasn’t any higher on the USB 3.0 controller.

Moreover, USB 2.0 drives can get much faster if you connect them to a USB 3.0 controller as the Corsair drive showed. We should acknowledge the EtronTech controller’s excellent work, especially as USB 2.0 mode isn’t a priority for it. It delivered high USB 2.0 performance compared to Intel’s USB 2.0 controller which is considered rather fast.

Connected to the USB 2.0 controller, the two USB 3.0 drives that we tested were about as fast as one of the fastest native USB 2.0 drives, the Corsair Survivor GTR. It must be noted that the Kingston DataTraveler Ultimate 3.0 was somewhat slower than its opponents, especially when reading small files.

When it comes to writing via USB 2.0, the Kingston was unrivalled with small files. It was twice as fast as the Corsair Survivor GTR which was second. The Kingmax ED-01, being good when reading via USB 2.0, can show a high speed of writing with large files only. It was much slower than the Kingston and Corsair when writing other files and was even outperformed by the humble ADATA in the MP3 pattern.

When connected to their native USB 3.0 interface, the Kingston is faster at reading large and medium files whereas the Kingmax reads small files better. The Kingston is also unrivalled in terms of writing, outperforming its opponent by 50% when writing a single large file. The gap is even larger with small and medium files.

Overall, the Kingston DataTraveler Ultimate 3.0 delivers excellent performance when writing files of any size, which is its main advantage. On the downside, besides its big case and high heat dissipation, is the low speed of reading files, especially small ones, in USB 2.0 mode. This drive may also require additional power for USB 2.0 connection. It is not handy to carry a rather big flash drive together with a power cable.

Well, there is already a second generation of DataTraveler Ultimate 3.0 drives which do not need additional power when connected via USB 2.0. Their specs are even more impressive: up to 100 MB/s at reading and up to 70 MB/s at writing.

The Kingmax ED-01 has advantages of another kind. It never fails at reading (even in USB 2.0 mode) and has a compact case. Its price is going to be more affordable, too. However, you should be aware that this flash drive is very slow when writing small and medium-sized files.

Summing everything up, we can say that, even though USB 3.0 is undoubtedly faster than USB 2.0, the real performance of USB 3.0 drives depends not only on the interface but also on their flash memory and controller. If a flash drive slows down to below 1 megabyte per second when writing small files, the newer interface won’t save the day. In other words, USB 3.0 will surely help reach higher speeds of reading and writing large files, but you can’t be sure about small ones. And with the fierce price competition among flash drive makers, it is quite possible that we’ll soon have the same situation with USB 3.0 products as with USB 2.0 ones where there is one fast model to two dozen slow ones which cannot fully utilize even the decade-old interface.