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Old Feb 13, 2010, 1:48 PM   #11
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I don't think that's what he's saying, Dave. I read this excerpt as the device is only drawing extra power from the USB 2.0 port; the data is still going though the ExpressCard slot.

Mike
The data is going through a USB 2.0 port. According to the article he's simply using an adapter, not a PC board, to allow the drive to use that port.

For example, I have a USB 1.0 port that allows me to use USB 2, but when I DO use USB 2 drives, they function at the same speed as USB 1.

This test is by it's very nature completely flawed. Credit to the author for giving us the real details - Nevertheless, a completely flawed test.

Dave
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Old Feb 13, 2010, 2:02 PM   #12
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He was using the USB 3.0 part on the ExpressCard for the data. But, something was flawed with the test (since it just doesn't match up to what I've seen with tests of these drives). My guess is that some type of software he was running on the test laptops was the culprit, or that particular ExpressCard had a driver issue of some type.

The separate connection to a USB 2.0 port was for power. Basically, that drive ships with a USB 3.0 cable and a USB power cable. If you're using a USB 3.0 port that doesn't provide enough power to power up the attached drive, then you can plug an extra cable into a "reliable" USB 2.0 port and draw power from it (one end plugs into a USB port, and the other end plugs into a power connection on the drive).

You can see photos of those cables in this listing (use the "image viewer" and you can see larger sizes).

http://www.newegg.com/Product/Produc...82E16822148529

That's the exact same way some of the third party portable drive enclosures work. For example, this one:

http://www.siig.com/ViewProduct.aspx?pn=JU-SA0312-S1

If you look at the included contents, you'll see both a USB 3.0 cable and a power cable (which can plug into a USB port on one end, and a power connection on the enclosure on the other end). You'll see it discussed in it's manual here:

http://www.siig.com/Files/Manuals/0008/04-0608A.pdf

But, it's only needed if the USB 3.0 port you have the drive plugged into is not providing enough power to power up the enclosure.

Most USB 3.0 ports on a PC probably would (as most 2.5" laptop drives are relatively low power devices), and all most smaller USB portable drives consist of is a USB attached enclosure with electronics for the appropriate connection (PATA or SATA) and a 2.5" laptop drive (because they're smaller, more shock resistance with lower power draw compared to 3.5" desktop drives).

But, apparently that Expresscard adapter does not provide enough power, hence the need for a separate USB attached power cable.
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Old Feb 13, 2010, 2:20 PM   #13
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He was using the USB 3.0 part on the ExpressCard for the data. But, something was flawed with the test (since it just doesn't match up to what I've seen with tests of these drives). My guess is that some type of software he was running on the test laptops was the culprit, or that particular ExpressCard had a driver issue of some type.
My bad, you're correct. But this raises another question - Which Express card? One is half the speed of the other...

ExpressCard USB 3.0 Card - 2 Port SuperSpeed USB 3.0 ExpressCard - StarTech.com

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Old Feb 13, 2010, 2:26 PM   #14
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The Seagate drive being tested in that article comes with an ExpressCard (they don't sell it without one yet). So, it's whatever card Seagate provides with that drive. ;-)
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Old Feb 13, 2010, 2:29 PM   #15
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Note that Seagate does say it uses an NEC chipset. But, virtually all of the USB 3.0 adapters use an NEC chipset (they were the first ones to introduce a USB 3.0 chipset and virtually all third party adapters you find are probably using it).

But, something must have been wrong with that test setup (drivers, software running on the laptops used, or something along those lines), since those test results do not match up to results I'm seeing in other tests.
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Old Feb 13, 2010, 2:30 PM   #16
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The Seagate drive being tested in that article comes with an ExpressCard (they don't sell it without one yet). So, it's whatever card Seagate provides with that drive. ;-)
If you look at the very bottom of the link I posted there are TWO versions of the Express Card, and one of them is half the speed of the other. Both are called "Express Card." In other words, one is rated at 2.5, the other at 5.

So, which card did he use for this review?

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Old Feb 13, 2010, 2:52 PM   #17
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You're miss reading it. You posted a link to an Expresscard that provides USB 3.0 ports (probably not the same one Seagate includes with their drive, but a similar card, and both are using an NEC chipset).

It's specs are talking about the generation of the slot it's plugged into on the laptop, not discussing two different cards.

"The maximum throughput of this card is limited by the bus interface. If used with ExpressCard Gen 1.0 enabled computers, the max throughput is 2.5 Gbps. If used with ExpressCard Gen 2.0 enabled computers, the max throughput is 5 Gbps."

http://www.startech.com/item-specs/E...d-Adapter.aspx

The newer 2.0 spec is faster. But, I doubt the difference between the specs would account for the slow speed the tester was seeing if he was using a laptop with a 1.0 version Expresscard slot (since even the older spec is plenty fast enough to support much higher drive speeds than he was getting from those tests).
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Old Feb 13, 2010, 3:34 PM   #18
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The newer 2.0 spec is faster. But, I doubt the difference between the specs would account for the slow speed the tester was seeing if he was using a laptop with a 1.0 version Expresscard slot (since even the older spec is plenty fast enough to support much higher drive speeds than he was getting from those tests).
2.5 Mbs would mean a theoretical increase of 6. Considering that theory never comes close to practice, the results (a three time increase) are in the ball park. Just look at a comparison of ratings in memory cards.

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Old Feb 13, 2010, 3:59 PM   #19
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That's 2.5Gbps, not Mbps. ;-)

That's over 312MB/Second (Megabytes per second) since there are 8 bits in a byte. That's *much* faster than any mechanical drive (and probably still faster than even the very fastest SSDs, although some of the higher end SSDs are getting close to that speed now). Also, keep in mind that you're limited by the speed of the SATA interface on the drive, even if you did have a drive that exceeded that much bandwidth (and most drives are now using a 3Gpbs SATA interface). We should start seeing some drives using a 6Gbps SATA interface soon though (and I suspect we'll start seeing some of the newer high end SSDs able to take advantage of speeds faster than a 3Gpbs SATA interface allows sometime later this year). So, in that case (very high end SSDs), a slower ExpressCard slot could potentially become a bottleneck at some point.
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Old Feb 13, 2010, 4:35 PM   #20
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That's 2.5Gbps, not Mbps. ;-)

That's over 312MB/Second (Megabytes per second) since there are 8 bits in a byte. That's *much* faster than any mechanical drive (and probably still faster than even the very fastest SSDs, although some of the higher end SSDs are getting close to that speed now). Also, keep in mind that you're limited by the speed of the SATA interface on the drive, even if you did have a drive that exceeded that much bandwidth (and most drives are now using a 3Gpbs SATA interface). We should start seeing some drives using a 6Gbps SATA interface soon though (and I suspect we'll start seeing some of the newer high end SSDs able to take advantage of speeds faster than a 3Gpbs SATA interface allows sometime later this year). So, in that case (very high end SSDs), a slower ExpressCard slot could potentially become a bottleneck at some point.
This is quibling over my posting the wrong acronym. It's STILL only a 6 fold increase over USB 2, and THAT is well within what we can expect from a test.

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