How to Match USB Ports & Controllers?

[JorgeA]

Hello,

Some weeks ago I went to plug in my external hard disk for a backup into the place where I normally connect it, and I received a message that I hadn't seen before: "This USB device can perform faster if you connect it to a Hi-Speed USB 2.0 port."

The odd thing is that this had not happened before. Which leads me to two questions:

1) Why would the computer all of a sudden decide that a USB port that was just fine for a USB 2.0 device, was no longer suitable?

2) When I went into Device Manager to find a USB 2.0 port where I could plug in the HDD, I saw a list of eight "Host Controllers," including two USB2 controllers, and eight "USB Root Hubs." Now, I have six physical places where I can plug in a USB stick. I imagine that my Pocket Media Drive (it's an HP computer) and the built-in Media Reader account for the other two. But the question is, how can I determine which two are USB 2.0, so that I can plug the HDD into them? Is there, or can I draw up, a schematic indicating which physical USB ports correspond to which controllers and root hubs?

Thinking about this -- and to make things even more confusing -- I now remember that the external hard drive used to be connected to a USB hub, which was then connected to the back of the computer. This worked great for several months, saving me a front USB port. But then one day the PC started having trouble finding (recognizing) the external HDD *when it was connected to the hub.* Now the PC never does find the HDD when it's connected via the hub, although it does find the drive when it's connected directly by itself -- and other devices do get found when connected to that hub?!

This wouldn't be such a big deal, except that now when I do a manual antivirus scan, if the external HDD is plugged in the scan takes like 26 hours to complete!! It used to finish up in a couple of hours up until recently.

What the heck?? Any ideas?

--JorgeA

[jaclaz]

Generally speaking, motherboards EITHER have USB 1.1 OR have 2.0 USB ports.

BUT is a known fact that (and don't ask me WHY - I am just reporting what myself and a number of other people experienced) the ports on the back (the ones DIRECTLY soldered to the motherboard) usually perform MUCH better than "front" ones.

It is probable that this is due to either the extension cable from the motherboard to the actual port or, maybe to a "different" USB controller used for the front ports, many may motherboards have problems booting off the front ports.

The usual advice is to ALWAYS use a port in the back for "high speed" devices such as external hard disks.

There are several tools to identify the bus/controller, a few are listed here:

http://www.boot-land.net/forums/index.php?showtopic=4661

Tools like SIV or SIW:

http://rh-software.com/

http://www.gtopala.com/

will also do, but even using Device Manager should be enough for a base view of how the buses are connected.

This:

http://www.nirsoft.net/utils/usb_devices_view.html

may be useful to clear the Retgistry from obsolete entries.

jaclaz

[dencorso]

1) Why would the computer all of a sudden decide that a USB port that was just fine for a USB 2.0 device, was no longer suitable?

It can be poor electrical contact (due to oxidation or, more rarely, wear).

Try the following: turn off the machine and unplug the power cable (if a desktop) or remove the battery (if a laptop/notebook). Then plug in fully and remove the usb cable (or device) from the port some twenty or thirty times in rapid succession, just to rub the contacts together (hopefully removing some oxidation from them). Remove the cable (or device) and turn on the machine again. After it finishes starting windows, plug the device/cable in again. Often you won't receive the "This USB device can perform faster if you connect it to a Hi-Speed USB 2.0 port." message again, at least for some time.

[jaclaz]

My knowledge may be a bit outdated, but in my day we used to CLEAN the contacts, by rubbing them with a contact cleaner, instead of fiddling with connectors pushing and pulling them "some twenty or thirty times in rapid succession"

You must be living in a very humid environment if you experienced USB contacts oxidation however.

jaclaz

[JorgeA]

jaclaz,

Thanks for the links to these programs. I downloaded SIV; already had USBDeview. (I also have a different one, named USB View.)

Of these three programs, SIV gives the most details. But unfortunately none of them really solves the mystery, which is:

According to all of them, I have a 4-port USB hub plugged into Port 4 of Hub 2, which is associated with a USB EHCI Host Controller. (SIV reports that I have two EHCI controllers, and six UHCI controllers, which matches what I'd seen before.) That is correct -- I do have a 4-port Dynex hub plugged in there, in the rear of the case. In fact, I also have a media card reader connected to one of the ports of that 4-port hub, into which I have inserted a CompactFlash card yielding 3.99GB of ReadyBoost capacity. So far, so good. Everything suggests that I'm dealing with a USB 2.0 port there.

Here's the problem: as an experiment, I shut down the system and unplugged the hub, left nothing in the USB port, and then turned the PC back on. After it finished the startup process, I then plugged in my external HDD to that same physical USB port where the hub had just been -- and I got the "This device can perform faster" message again, as if the same physical USB port that minutes before had been identified as 2.0 were now slower than 2.0.

So I stopped the device, unplugged it, then plugged in the 4-port hub with the card reader and the CF card -- and my ReadyBoost came back, with no message about a device being able to perform faster if blah blah blah.

Now let me add to the confusion. If I connect the external HDD to the same Dynex hub where the card reader with the CF card is plugged in, the HDD doesn't even get recognized! (The 4-port hub has its own power supply.) But it used to. Could it be the external HDD's USB cable? If so, can I just use any USB cable with the right type of connectors? (I don't want to fry the HDD.)

A couple of weeks ago I tried the same experiment with another 4-port hub, and the same thing happened. I'd thought that maybe the cheap hub was messing up, but now it's two from different brands that are behaving the same way.

Any ideas? In the meantime, I'll try dencorso's procedure and report on what happens.

--JorgeA

P.S. It would be nice if there were a program that told you plainly, without a lot of distracting technical detail: "O.K., the top left USB port in the rear of your computer case is USB1.1 and belongs to Hub 2. The top right port is USB2.0 and belongs to Hub 4. The bottom left port is also 2.0 and goes with Hub 1, and the bottom right port is 1.1 and goes with Hub 3." Does anything like that exist??

An even further frustration is that apparently each of these Hubs, Controllers, or whatever, is associated with two or more "ports," for a total (on my computer) of 24 "ports." Yet I only have 6 places on the computer into which I can actually connect a USB device. (There is an integrated card reader, but it only takes up a single port in one Hub.) So how or where do the extra 18 "ports" come into play? How can one make use of them?

Try the following: turn off the machine and unplug the power cable (if a desktop) or remove the battery (if a laptop/notebook). Then plug in fully and remove the usb cable (or device) from the port some twenty or thirty times in rapid succession, just to rub the contacts together (hopefully removing some oxidation from them). Remove the cable (or device) and turn on the machine again. After it finishes starting windows, plug the device/cable in again. Often you won't receive the "This USB device can perform faster if you connect it to a Hi-Speed USB 2.0 port." message again, at least for some time.

Thanks dencorso, as I wrote to jaclaz I will try this and report back.

--JorgeA

[dencorso]

@JorgeA: Observe that if all ports are USB 2.0, you will have one EHC for all of them (at least) but also one UHC(or OHC) for each pair of ports. What decides whether the port wil behave as a USP 2.0 interface (and use the EHC) or as a USB 1.1 interface (and use the UHC/OHC) is dependent on how the device just plugged in is detected. And when a 2.0 device is improperly detected, the system falls back to 1.1, regarderless of the fact bothe the port and the device *are* 2.0! On the other hand, USBView numbers the ports consistently, so if you use a 1.1 device, such as a mouse, you can plug it into one port at a time and thus map the 1.1 port numbers to the physical port connectors in your machine. Doing likewise with a pendrive or any other 2.0 device will help you to find out the USBView numbers of the same physical port connectors. Each physical port connectors must map to two different numbers, one under the EHC and one under one UHC(or OHC). Now, if you have a USB 1.1 motherboard with a USB 2.0 add-on card, then things get some more complicated.

@jaclaz: 70-80% relative humidity all year round... And the rain pours endlessy, too.

[jaclaz]

On the other hand, USBView numbers the ports consistently, so if you use a 1.1 device, such as a mouse, you can plug it into one port at a time and thus map the 1.1 port numbers to the physical port connectors in your machine. Doing likewise with a pendrive or any other 2.0 device will help you to find out the USBView numbers of the same physical port connectors. Each physical port connectors must map to two different numbers, one under the EHC and one under one UHC(or OHC).

I may add that it is advised to do this with the Registry cleared (or a new installation).

jaclaz

[JorgeA]

@JorgeA: Observe that if all ports are USB 2.0, you will have one EHC for all of them (at least) but also one UHC(or OHC) for each pair of ports. What decides whether the port wil behave as a USP 2.0 interface (and use the EHC) or as a USB 1.1 interface (and use the UHC/OHC) is dependent on how the device just plugged in is detected. And when a 2.0 device is improperly detected, the system falls back to 1.1, regarderless of the fact bothe the port and the device *are* 2.0! On the other hand, USBView numbers the ports consistently, so if you use a 1.1 device, such as a mouse, you can plug it into one port at a time and thus map the 1.1 port numbers to the physical port connectors in your machine. Doing likewise with a pendrive or any other 2.0 device will help you to find out the USBView numbers of the same physical port connectors. Each physical port connectors must map to two different numbers, one under the EHC and one under one UHC(or OHC). Now, if you have a USB 1.1 motherboard with a USB 2.0 add-on card, then things get some more complicated.

dencorso,

That was a highly informative paragraph, thank you.

Have yet to try the procedure you described involving shutting off the power, but I did match the physical ports to USB 1.1 and 2.0 controllers with the above procedure. I used a SanDisk Cruzer stick as the 2.0 device -- and the external HDD as the 1.1 device (seeing as I didn't have anything else that I knew the computer would consider a 1.1 device). (My keyboard and mouse are PS/2.)

I'd actually tried doing this several weeks ago, but what threw me off -- and this is where your description came in to save the day -- is that the hub and port numbers changed (unpredictably, for all I knew) whenever I connected a USB 1.1 vs. a 2.0 device in the very same jack. Knowing that they're designed that way helped me to make sense out of what was going on.

So apparently ALL the available physical USB ports on my Vista PC are USB 2.0. Which leads me to wonder if the culprit is in fact the cable to the external HDD, or maybe something having to do with the drive itself?

Now, while we await the results of the "connect and disconnect repeatedly" test, I have another question about USB port number assignment:

USB View, USBDeview, and SIV all report that my Root Hub 8 (or 7 in the case of SIV, which starts with 0) has a total of 8 ports. Using your mapping procedure, I was able to identify (connect to) 6 of them. Two are in the front, a third one is for the Pocket Media Drive, the fourth is for the built-in card reader, and two more are in the rear (top left, top right). (The bottom left and bottom right USB ports in the rear are associated with Hub 3.) Here's the question: How would one get to use the last two Hub 7 ports?

--JorgeA

jaclaz,

SIV is hands down the most complete system information tool I've ever seen -- tons of inner details about your PC. Thanks for pointing me to it.

How DO you find all this neat stuff?

--JorgeA

Edited July 21, 2010 by puntoMX

[dencorso]

USB View, USBDeview, and SIV all report that my Root Hub 8 (or 7 in the case of SIV, which starts with 0) has a total of 8 ports. Using your mapping procedure, I was able to identify (connect to) 6 of them. Two are in the front, a third one is for the Pocket Media Drive, the fourth is for the built-in card reader, and two more are in the rear (top left, top right). (The bottom left and bottom right USB ports in the rear are associated with Hub 3.) Here's the question: How would one get to use the last two Hub 7 ports?

I bet you have one unused USB header connector in your motherboard. The USB header connectors are two parallel rows of 4 pins (or of 5 pins), to which a eight-hole connector should be attached (this connector would be at one end of a cable that, on the other end has the usual two retangular female Type-A USB connectors, usually mounted in a rear-bay bracket, like this one. The pinout is not exactly standard so it's necessary to compare the pin positions on the cable you eventually buy with that of the header (according to your motherboard manual) to see if the bracket cable can be used directly or if some of the connector pins must be moved around by hand. Download your motherboard manual and locate the USB headers in it. Then open the case and look for your actual header connectors and find out whether I'm right and there is one unused. If so, and in case you decide to put it to use, then I can discuss it in more detail.

Changing subjects (well, not much): if your HDD is being detected as USB 1.1 in everyone of your USB ports, then something is wrong with its cable or, worse, with its internal USB controller. Try connecting it to another machine, whatever the OS it may have, just to see whether it also gets recognized as 1.1, and if so, change the cable.

Any cable with the proper connectors will do, but a shielded one is best.

BTW, which motherboard exactly do you use? I'd much like to look at its manual, too.

[jaclaz]

How DO you find all this neat stuff?

You won't like it.

http://www.911cd.net/forums//index.php?showtopic=16534&st=23

jaclaz

[JorgeA]

How DO you find all this neat stuff?

You won't like it.

http://www.911cd.net/forums//index.php?showtopic=16534&st=23

jaclaz

Uh-oh, I'd better stop asking questions right now!

Some secrets are better left undiscovered...

--JorgeA

dencorso,

Wow, thanks for all the details. Now you know what my weekend project will be!

BTW, which motherboard exactly do you use? I'd much like to look at its manual, too.

Here's what I found for my PC.

And, more specifically, there's this.

I tried the rapid connect/disconnect procedure. Unfortunately, I'm still getting the same result ("This device can perform faster if...").

I also tried using a different USB cable to connect the external HDD. Borrowed it from one of the USB hubs. Like the drive's original cable, it has a regular Type A USB plug to go into the PC and a mini-B USB plug to go into the HDD. But this time the HDD was not even found by the PC.

We'll try plugging in the HDD to a different modern PC, as soon as I convince my wife to allow an alien object to connect to her machine.

--JorgeA

Edited July 21, 2010 by puntoMX

[jaclaz]

as soon as I convince my wife to allow an alien object to connect to her machine.

An old trick of the trade tell her it is a new USB powered aromizer... or a new age ambience enhancer

At least mine used to fell for these kind of tricks, at least till the day I zapped accidentally one of her PC's ports

jaclaz

[dencorso]

Great, JorgeA!

Now that I know which board you have, I can tell you that:

1) It uses Intel ICH9R southbridge, which has internal support for 12 USB 2.0 (forget the other controllers, how many EHC ports does USBView find, regardless of mapping?), which may or may not be *all* available in that motherboard, so that's your *upper* limit.

2) HP says there are 4 USB ports in the back-panel, soldered directly on the motherboard and two USB ports in the front pannel, plus the Pocket Media Drive and the Card Reader... that makes 8 USB ports in total.

3) HP says there are three USB 2.0 headers supporting 6 USB ports or devices, and since we can account for just 8, of which we should subtract the 4 on the back (which are soldered, so they don't have headers), ergo you must have one free header supporting two further USB ports.

Now you'll say to me: one free header? two further ports? 8 + 2 = 10... didn't you start talking about 12 ports?

Yes, I did. But... HP also says there are one 1394a port in the back and one internal 1394 port header (for one further firewire port) inside. The ICH9R can control up to 12 USB 2.0 or 1394a ports in total. So here are the missing two ports.

Now you'll say to me: that means I can have also one further 1394a port, if I find that header? Yes, probably.

Here's what you have to do: the headers are in a single row on the lowermost part of the motherboard, just below the PCI connector. They have lables written in white fields, which are illegible in this photo (but the white fields are visible). Open the case read those labels and report. You can ignore any header that has a connector plugged in it. Only the unconnected headers interest us. I'm quite sure those two white headers, with two rows of 5 pins (of which one pin is missing) are USB headers, but probably the two black headers next to them also are and I bet they are used for the Pocket Media and the Card Reader. I bet one of the white connectors will be unused and the other is the one serving the two front USB ports. I'm think the 1394a header is the somewhat higher red header that is to the left of the two PCI-e x1 connectors, just about between them (so it's not shown in the attached picture snippet), but I may be wrong. That is up to you to find out. Take care not to disconnect anything, you just want to take a peek, at the moment, nothing more. A thin hand lantern is most useful to help on your task. Good luck!

[JorgeA]

as soon as I convince my wife to allow an alien object to connect to her machine.

An old trick of the trade tell her it is a new USB powered aromizer... or a new age ambience enhancer

Hmm, maybe I should have tried that, might have made it a lot easier.

I should report that it took some persuading, but I finally got permission to plug in the external HDD -- and we got the same old result as on my PC.

At least mine used to fell for these kind of tricks, at least till the day I zapped accidentally one of her PC's ports

Ouch!! I'll bet you had to do a lot of penance for that one. I know I would...

--JorgeA

dencorso,

Mystery solved! Amazing detective work, thanks!

First thing will be to check out the link you provided. Then I'll open the case tomorrow or Sunday, see how it looks in there, and get back to you. The machine could probably use an internal dusting anyway.

--JorgeA

[jaclaz]

Ouch!! I'll bet you had to do a lot of penance for that one. I know I would...

Well, actually the culprit (or - more accurately the one I pointed to as having created the short by wagging her tail) simply got a couple less biscuits than usual for a few days.

Both the females (human and dog) never actually knew the truth.... but you know how women are, notwithstanding the dog's responsability for the accident, she "sensed" something and I was told NOT to connect anything anyway, EVER AGAIN...

jaclaz