If you're having problems with USB ports, read on...

nthums

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A lot of posts on pin 10, but all need to read the USB specification, in particular the part on USB2.0.
Dare I say you all have it wrong.
In the pre-specification developed by Intel pin 10 was to be designated for overcurrent, but in the official specification it is for shield ground.
Prior to USB2 there was no requirement for the cable to be shielded, but with the much higher data rates under USB2 the cable needs to be shielded to stop errant noise from climbing on to the data lines and forcing misreads and re-requests of data. The continuous connection of the shield is accomplished via the metal shell of the connector. That is you have the 4 pins inside if you look in the end, plus the outer metal shell. That spec is to be followed from origin to termination with the exception being at those points where the wires break out without a USB2 connector and there they will be wired to the device. It has been a long time since I went over this with the board and read the spec, but I'm now thinking there may have been one exception and that was for a mouse. Check if you like.
It became a question for me when I discovered my case was not using pin 10 and I decided to check the facts. And despite it seems to have fixed a situation for some of you, one user in the forum for my case had an issue with front port not working for something, I no longer remember what, he picked up on my posted findings and posted back that modifying the case cable to connect fixed his problem. In our case, the harness floats at both ends, that is at the front port where the shell of the plug makes contact, it was connected to nothing.

I can not tell you who did not follow the USB Board Specification in each of your situations. It is possible the MOBO was not designed properly. One easy way to verify it is, check that pin 10 on the MOBO headers use the same physical plane as the shells for the USB connectors on the back of the board. They all should be signal ground, which may or may not be the same as power ground.
It might be your case maker if the ports for the front were installed by them.
Nor can I tell you exactly how much impact will occur if your shield is not properly terminated. It can vary according to the device plugged and it's demands. If it is USB 1 or 1.1 it should have no real effect because shielding was not required then. It will in part depend upon how much noise is getting to the data lines forcing resends. BTW, the data lines are a twisted pair.
Norman :shocking: :shocking:
 

ex_forum_user_3

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USB needs 4 wires and that's it.
Pin 10 should not be connected and is useless.

Intel's spec, yeah right, let's start about that one.
If we would follow Intel, we wouldn't be able to use high powered systems at all.

In case you don't know, the metal of USB is connected to ground of your CASE, your motherboard is also by it's mounting holes.

The connection from board to usb port is 4 wires, and 4 wires only (per port).
You are DEAD wrong (so is Intel :lol_anim: )
 

nthums

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Before you run your mouth anymore and show your lack of knowledge do as I said. Go to the "USB Specification Board", no not the Intel stuff, it was never accepted in any manner.
The only thing you have correct is that the rear jacks have the shell connected to the ground plane (shield ground and power ground) of the MOBO and the case.
Nearly all front mount jacks are not mounted to metal of case, but in plastic bezel. And thus defeating the shielding on the internal wiring as well as anything you plug in to a front jack.
I had lengthy Q&A sessions with a couple of the guys on the board to make sure I read it right.
If it does not work this way, your MOBO manufacturer ignored the specification.
Some very early USB2 MOBO were released before completion of specification, mostly Intel, and if still available, some sites selling the internal harness came with pin chart.
Go read the USB Board specification and by Board I'm not talking forum. This would be more like Board of Directors, made up of a few manufacturers to come into agreement with a specification for manufacturer.

:wall:
 

rhradacut

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Also easy to remove wire from plug this way. Insulate the bare end and tie it out of the way.

                     
 

nthums

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henry, at least you are thinking ahead and not defeating being able to undo your work.
I find the picture a bit strange. Any of the pins can be removed that way and replaced if careful not to bend. And if you run across one of those early non-conforming to anything MOBO, mostly Intel design, you will be able to swap all of the pins around to meet needs.
Was this some special wire to meet needs of two jacks, rather than two individual lengths of USB cable?
The picture implies that because of the much heavier appearance of the red wire you are removing. Uncertain with old memory but think the power wires were either allowed or standard being one guage heavier than signalling twisted pair. At the opposite side is the appearance of a much heavier wire. Is that two sleaved together from breakout point or what? I have seen a shortcut method for directly connecting shield braid directly to pin and this reminds me of it. It can do the job if shielding is not too big for pin. Most applications and terminations for USB shielding I've seen use a pigtail device the shrink solders to the shielding and then has the appropriate size wire coming out for the pinning.
Maybe it is just the perspective of picture, but I'm curious.
 

rhradacut

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That's just some picture I found doing some web browsing on the subject. The wires in this picture are not even in the right order, correct is red-white-green-black. As far as the shield goes on my MSI bracket wires it's floating, no connection on either end. I should have included the following in my last post but here it is now.
I tried to make it as simple as my brain can function and still convey the info needed. :grin:

  In this pic you are looking at, left to right 2-red, 4-white, 6-green, 8-black and no wire at 10.
From this view of plug on opposite side would be lt. to rt. 1-red, 3-white, 5-green, 7-black and no wire at 9 (key)
When plugged into header on MB red will be on the left.

 


   
 

nthums

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Your connection is what quite a few have gotten when it comes to case wiring, and unfortunately it is wrong according to USB Board specification. After reading specification, I contacted members of the Board to make sure I understood it correctly. Not all manufacturers are members of the Board, but all were expected to comply with the specification. The specification contained many pages of test procedures along with signalling & power specifications, etc. Pretty complicated stuff. I was drew into a bit because it made use of CHIRP, compressed high intensity resolution pulse, something I had not seen for nearly 30 years. A special technique used in military RADAR to give added information of targets.
The shielding specification added with USB2 was like a footnote compared to the rest of it. Besides the very short paragraph adding that requirement there were a few partial pages showing pictures of connections. That small but very important piece of information was near lost among the near 500 other pages and suspect it was just overlooked by some manufacturers.
The Board required full compliance of specification to label product USB 2. But are near powerless to force someone into compliance.

After reaching a satisfactory understanding of USB 2 specification, it was my thought that maybe they would emphasize the shielding connections a bit with the next release. The USB 1 & 1.1 specification is much smaller mostly because timings and frequencies to carry signals are much smaller. And no shielding is required. Since USB 2, the specification for USB Mobile was completed. But it is mostly a continuation of the 2 specification. No mention of shield requirements whatsoever, but is required because of the mention in the Mobile specification that it needs to comply with USB 2.

I have not fixed my case wire since I hardly ever use those jacks. And they would meet USB 1 & 1.1 specification. And in the back of my mind is a suspicion. Even though all is supposed to be backward compatible, I have this thought that the processing, the coding and decoding of the signals, will be interfered with by noise. Possibly extra requests to make certain the processing got it's read correct.
And this labeling of USB2 packaging that the device is up to 480Mb/s, well that is a lie. The only 480 in the specification as I recall is the frequency of the processor. Bandwidth is shared, not in the way we might think, like one device gets the full amount, then it switches to next device, and so on in a time sharing manner. Instead each device is limited to a predetermined amount of total and it will never operate any faster than that, even if it is the only plugged device. This is easily verifiable if bandwidth for each device is shown in your device manager. If you have one device on root hub, you can remove devices from others and notice it does not change. If you have multiple on one hub, plug each device separatly and add up percentages. It will equal when all are plugged to that same hub. My understanding is this is done so no one device will take the full bandwidth thus maybe blocking something as important as your mouse or keyboard. Although I read some of it was done via ini files/install files, some of it must be registry files.
It read that the maximum allowable for high bandwidth devices such as HDD was set low enough that you could plug two such devices and have enough left over for high priority devices such as keyboard and mouse. Interpret that as meaning, 480 divided by 8 = 60MB/s.
You will never see your DVD or HDD transfer at 60MB/s. If you know how to alter files, you might do that, but it might lead to disastrous results with nothing left over for other devices. Since it is limited to less than half with reserve for some other stuff, figure somewhere in the mid 20MB/s. Back to bits, that is mid 20's, 25 times 8 = 200Mb/s would be more truthful on the packaging.

Seeing what a mess some manufacturers had made of specification, it was my hope that all would be fixed at USB3. It is now very doubtful that we will ever see USB3 unless there is a major leap in that technology. eSata seems to be taking over if you can not find SCSI affordable.
There have been some developments that put manufacturers in a hard place, having to pay high royalty fees tied into device pricing. Manufacturers have been able to do end runs around some of that technology. Intel's RDRAM was such, replaced by DDR RAM. And USB was brought on to avoid FireWire. In the area of HDD's, SCSI has been around for a very long time and was used in older Mac's exclusively. The price forced work in the ATA development. Even the HDD manufacturer had to pay fees for building SCSI drives. As ATA drives became a better alternative for those needing really fast arrays such as servers, it forced SCSI to develop faster. USB against FireWire did the same. Competition has been good for the PC user, except in one area, my opinion. That is Blu-Ray because I don't see the tremendous difference over HD except in the price. This link for a good chart on where speeds are at might be interesting. If there is not some technology highly licensed in the fiber area, it would be my guess that SATA will eventually use that.
http://en.wikipedia.org/wiki/Serial_ATA#SATA_and_PATA
Scroll down.
 

gordym

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My MSI 975x would recognize the USB ports for 1.0 only. When I enabled 2.0 the internal USB header would die, but the rear external ports worked just fine. I needed the internal ports to work as well as th rear ports because I connect my 7" integrated LCD touch panel to the internal USB (Zalman HD160XT home theater case). I checked the usb header connector and sure enough, Pin 10 has a jumper wire to the ground pin. I removed the jumper wire and everything works fine in USB 2.0 mode. Thanks!
 

Fredrik

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Here is another thing which is related and which some may have been hit by:
http://support.microsoft.com/kb/817900

Another Windows thing.


Off:
Front panel, card readers, Logitech, Windows sums things up pretty well. Oh, and this 10 th pin.
 
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