USB 3.0 transfer speed slow

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snejsnej

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Hello,

Apologies in advance if this is not the right forum.

I purchased a Kingwin Dock-Master hard drive docking station, as well as a Seagate 1.5TB 7200 HD to use with it. The docking station is connected to my computer via USB 3.0.

I just started a straight file copy (drag & drop) from one hard drive to the Seagate in the docking station, but the transfer speed is very slow --> sustained copy speed of about 65-66 MB/second, which seems more like USB 2.0. How can this be fixed?

Thanks in advance for any help.

Jens
 
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You should remember that the data is transferred to the destination, only as fast it is being read off the source.

USB 2.0 has a maximum theoretical speed limit of 60 MB/s. Actually, it is only today, 8 years...

snejsnej

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Hi Herr_Koos & Collie147,

The motherboard is definitely USB3.0 enabled; there are separate connectors for USB 2.0 and 3.0.

I'm sorry, but I just arrived at work and won't be able to tell you which mobo it is until I get back later today. In any case, the USB 3.0 is built in, it's not a PCI card.

Thanks!
 

ksampanna

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You should remember that the data is transferred to the destination, only as fast it is being read off the source.

USB 2.0 has a maximum theoretical speed limit of 60 MB/s. Actually, it is only today, 8 years after the launch of USB 2, that USB 2 devices are able to fully exploit this speed (even then, there are not too many which can do this). Most of the USB 2 devices today max out at 30-35 MB/s. I've already given the reason for this, the read-write speeds of devices bottlenecks the transfer process.

So for USB 3, don't expect speeds of 400 MB/s +; since even though the data could be transferred at that rate, it cannot be read off the source HDD or written to the external drive at the same rate. Now if you were to hook up a superfast SSD to the dock, & also had a similar speed SSD in your system, then the transfer process would be definitely faster, since both drives could read & write lighteningly fast.
So it is more likely that the transfers you are doing are bottlenecked by the storage drives, in particularl, their sequential read/write speeds; not due to the fault of USB 3.

 
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snejsnej

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Thanks ksampanna,

Well that's a bit of a wake-up call; I have to admit, I feel like a bit of a sucker for the big marketing machine.

In any case, I just performed a file copy from one internal hard drive to another (both @ 7200), with a sustained data transfer rate of about 106 MB/sec. This is also lower than what I thought it would be; on the other hand there aren't many individual large files, but rather many smaller ones which tends to slow things down too.

Nevertheless, shouldn't the USB 3.0 connection be able to move data at least close to this speed? If the bottle neck is the read/write speed of the HDs (again, around 100 MB/sec), where are the other 30-35 MB/sec hiding?

Thanks
 

Computerrock1

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My hard drive in Sata only goes an avg. of 90 MB/S, the usb 3.0 utilizes the full speed of the hard drive, like ksampanna said, if you had an ssd hooked up to the usb 3.0 you would be seeing much faster speed. The Hard drive is going as fast as it can, not the usb connection.
 

snejsnej

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Computerrock1: Right... so the hard drive is going at ~100 MB/sec but the USB 3.0 is only going at ~65MB/sec. Shouldn't the USB 3.0 transfer speed be close to, or equal to the HD speed?
 

ksampanna

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The only reason I can think of is that both the internal drives are connected by SATA, which would optimize the transfer process. Also are you sure that there are definitely two internal drives? Else you just might've transferred data from one partition to another, which whould no doubt be speedy, since it is being read & written to the same drive itself.
 

snejsnej

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Yes, two physically separate drives in the enclosure. They're both SATA which, if what you say about optimized transfer is right, must be causing the difference in transfer / copy speed. This is a bit of a drag! I guess it only really makes sense to spend money on this kind of peripheral once prices for SSD come down, since only then will we be able to take greater advantage of the higher speeds offered by USB 3.0.
Thanks guys.
 

soloft

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I had the same problem as you when I bought an external drive over USB, except my internal HD runs at 5400 RPM, so it's slower than yours.
Addressing your question of where the other 30-35 MB/sec are hiding, USB 3.0 has a sizeable overhead that is likely hogging this speed. I don't know the specifics, but if you google about the overhead I'm sure you will find out some more.
Also, it sounds like you have multiple hard drives in your computer. If you want to increase the data transfer speed in general (via USB 2, USB 3, firewire, etc) you could make a RAID 0 array. That's what I'm doing, I've got another HD on the way from newegg that I'm going to RAID 0 with my other internal drive. I'll let you know how much the speed increases if you like.
 

MIDNITE14

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I HAVE A SYSTEM WITH THE FOLLOWING SPECS
15 250K OVERCLOCKED
ASUS Z68 MOBO
CRUCIAL 16GB DDR3-1600
CRUCAIL 64GB/6GB/S SPEED SOLID STATE HDD
I PLUGED A Emtec International USB 3.0 FLASH DRIVE INTO MY BLUE USB 3.0 PORT
AND THE SPEED IS HALF AS FAST AS A USB 2.0
 
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