any bottleneck issue with usb 3.0 pci adapter on old dell desktop system?

aigomorla

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yes and no...

PCIe 1.0a, with a per-lane data rate of 250 MB/s and a transfer rate of 2.5 gigatransfers per second (GT/s).

vs USB3.0 which is 5gb/s ... so almost double...

HOWEVER...
the no is can u find a USB3.0 device which is that fast to begin with?
Because 250 MB/s and a transfer rate of 2.5 gigatransfers per second (GT/s) is in SSD territory... And not cheap SSD's either.. but your mid to high grade.
Also thats READ speed... you would need more then 2 in Raid to max it out on the Write territory.

So unless ur considering on Raid 0 2xSSD's on a USB3.0 enclosure.. id say no.
 
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kreactor

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so real world advertised 3.0 usb transfer speed are not really attainable ?

but this pci card would not be a "bad" purchase to move to usb 3.0 external storage vs paying about 20% less for usb2.0

thanks!
 

jkauff

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You'll like USB 3.0 external storage. I have five 3TB WD My Book drives (Staples carries them, and they often have 20% off one item coupons) and their transfer speed is greater than my SATA3 to SATA3 transfers. If your MB mfg offers a "Turbo USB 3.0" utility (my Asus does), use it. It really does speed things up.
 

Cerb

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so real world advertised 3.0 usb transfer speed are not really attainable ?
No. USB 2.0 would never get 48MBps, either. That's marketing for you.

Still, there is no good reason to get a PCI-e USB 2.0 card. A USB 3.0 enclosure can get near-internal speeds for HDDs, and if the moon is aligned right, 400MB/s reads from an external SSD have been measured (not all chips or firmware implementations can do that, but you should pretty much always be able to get >100MBps from a USB 3.0 SSD). Also, USB 3.0 is not deathly slow for smaller transfers, like USB 2.0 was. In your case, with PCI-e 1.0, you should be capped somewhere around 220MBps.
 

aigomorla

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so real world advertised 3.0 usb transfer speed are not really attainable ?

but this pci card would not be a "bad" purchase to move to usb 3.0 external storage vs paying about 20% less for usb2.0

thanks!

they are attainable..

however in your case seeing how old your system is... i dont think you will ever reach them.
Not unless u wanted to drop more money on a removable enclosure that costed more then your entire PC.

ie... 2x240gig Sandisk Extreme 2's = 700 dollars after tax + shipping.. would bottleneck your PCI-E lane on a USB3.0 card.


this is why i said yes and no..

yes you can bottleneck it... however no... as in it would cost you more then your PC to do so, and wouldnt be worth it.

So i also vote u buy a usb3.0 card... u will still get better latency and bandwith on it, even tho you bottleneck it.
 
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