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Old 03-16-2011, 06:58 AM
Vorpal Blade Vorpal Blade is offline
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USB Cables - 1.0 vs. 2.0

I have a bunch of USB cables some of which could be 4-5 years old, maybe more. Some of them, then, are likely to be 1.0 while some are 2.0. Does it matter, i.e., is there a performance hit using the 1.0?

Devices I have connected (via a powered USB hub) include an external HD drive, a printer (Kodak 6150, if it matters), and a set of self-powered speakers. Occasionally a camera.

TIA for answers and comments.
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Old 03-16-2011, 07:07 AM
psychonaut psychonaut is offline
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USB 1.1 and USB 2.0 use identical cables. Any cable which fully complies with the USB 1.1 standard will work with USB 2.0 devices at full speed. Unfortunately, a lot of cheaper cables manufactured in the USB 1.1 era don't contain the level of shielding mandated by the standard; this wasn't a problem for the relatively slower USB 1.1 but does affect performance of USB 2.0.

Note that USB 2.0 has been around since 2000, so your 4-5-year-old cables are probably OK.

Last edited by psychonaut; 03-16-2011 at 07:08 AM.
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Old 03-16-2011, 08:22 PM
Digital is the new Analog Digital is the new Analog is offline
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Quote:
Originally Posted by psychonaut View Post
USB 1.1 and USB 2.0 use identical cables. Any cable which fully complies with the USB 1.1 standard will work with USB 2.0 devices at full speed. Unfortunately, a lot of cheaper cables manufactured in the USB 1.1 era don't contain the level of shielding mandated by the standard; this wasn't a problem for the relatively slower USB 1.1 but does affect performance of USB 2.0.

Note that USB 2.0 has been around since 2000, so your 4-5-year-old cables are probably OK.
You are technically correct - the best kind of correct!

I've noticed that many people don't realize that USB 2.0 does NOT mean high speed USB. You can be USB 2.0 compliant and only operate at full speed..as Psychonaut mentions.

If your real intention is to run high speed, then 1.1 era cables may not be good enough. I've certainly seen problems with that. The negotiation calls for a series of short pulses, called "chirps". The cables often are good enough for the chirps to be heard, and the host and client agree to go to high speed. But then they start transfering lots of data, and the cable doesn't "hold up". So you get data packet drops, timeouts, and eventually USB resets.


-D/a
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Old 03-16-2011, 10:40 PM
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And for anyone who isn't yet familiar with high-speed vs full-speed, that was an evil and confusing marketing decision made a long time ago:
http://www.photoxels.com/article-usb...ull-speed.html
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Old 03-16-2011, 11:21 PM
FuzzyOgre FuzzyOgre is offline
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I was kinda wondering this just the other day. I have a new motherboard to set up, and it has usb 3.0. I am curious if the interface between my flash card will be the bottle neck, or if its the cable, or what. My external technology is all usb 2.0.
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Old 03-17-2011, 12:56 AM
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Originally Posted by FuzzyOgre View Post
I was kinda wondering this just the other day. I have a new motherboard to set up, and it has usb 3.0. I am curious if the interface between my flash card will be the bottle neck, or if its the cable, or what. My external technology is all usb 2.0.
USB 3.0 does definitely use a different cable. The plugs are actually different, having extra leads, albeit backwards compatible with older USB devices. USB 3.0 has 9 pins (6 used for data), while USB 2.0 and lower have only 4 or 5 (2 used for data).
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Old 03-17-2011, 11:34 PM
FuzzyOgre FuzzyOgre is offline
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USB 3.0 does definitely use a different cable. The plugs are actually different, having extra leads, albeit backwards compatible with older USB devices. USB 3.0 has 9 pins (6 used for data), while USB 2.0 and lower have only 4 or 5 (2 used for data).
Thanks. I should have looked more closely. Ignorance fought!
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Old 03-18-2011, 04:34 AM
psychonaut psychonaut is offline
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Originally Posted by Digital is the new Analog View Post
You are technically correct - the best kind of correct!

I've noticed that many people don't realize that USB 2.0 does NOT mean high speed USB. You can be USB 2.0 compliant and only operate at full speed..as Psychonaut mentions.
Actually, I was a bit sloppy. When I said "full speed", I wasn't using the term in its technical sense, but rather in its informal one. Technically speaking, USB 1.1-era cables will work fine for USB 2.0 devices at the regular "full speed" and also at the faster, USB-2.0-specific "high speed", provided the cables have the amount of shielding mandated by the USB 1.1 standard. Unfortunately, many cheap cables are not built to spec, and therefore lack this shielding. Such cables will work at "full speed" but may not work at "high speed".
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