Dead USB Ports, Fore n' Aft. How to test?

**kopfjaeger** · April 28th, 2011, 06:58 PM

Hello Gents,

The on-board USB ports to this board appear to be dead, however the board seems otherwise to function normally. What could be the cause and the remedy?

In the interim, how do you test a USB port with a digital multitester (set for 5V DC or AC?).

HARDWARE / SOFTWARE SPECS

Second-hand board, ASUS P4G533-LA / 1TB DDR 400 RAM,

Fresh install of Win2000 /SP4.

The ASUS drivers were VGA, RealTek Sound and 4-in-1 Chip.

I CANNOT find a tech manual for this board at all, so I cannot check the pin-outs for the front panel USB pins. That being said, the cable that the mainboard and forward USB ports are connected by is wired in this manner:

R-W-G-B-B
R-W-G-B-Key

CMOS Settings

USB Legacy Support has been AUTO / Enabled with still no recognition of USB devices plugged in to the on-board USB ports (forward USB ports connected by means of twin 4-pin cables to front panel USB ports (R-W-G-B).

OTHER USB

I doubt that this is completely a software issue, as I have installed, in turns, NEC, SIIG and VIA 5-port PIC-USB cards. Once their drivers are installed, they seem to function normally.

QUESTIONS

1) What might be the cause of a failure of onboard USB ports to operate?

2) How do I test them using a digital multitester?

My thoughts are to take a standard paperclip, straighten it, stick it in the female end of the Main board-to-front-panel USB cable and test for 5V coming out of what should be the power pins, and to ensure the other pins are not putting out voltage.

Is this correct?

And while it seems a very basic question, I am assuming that the 5Volts associated with the USB port is DC, not AC.

Am I wrong here, since a lot of USB devices are battery powered.

(Bones shouts with some venom: 'D*mmit Jim, I'm a tinkerer, not an Engineer!")

Analysis Spock?

**Steve R Jones** · April 29th, 2011, 04:58 AM

Win2k isn't helping the situation...But most mobo's have seperate drivers for USB.

**Chuckiechan** · April 29th, 2011, 12:43 PM

Dude, you have a Tetrabyte of ram? With Win2K you are only using a portion of it... What a waste!

I'd load Win7 on and probably solve your problems if the board isn't way obsolete.

If not, I'd definitely check with a voltmeter - but off the USB ports on the board itself.

Lastly, I'd try to find a systems disk by hook or by crook. (advertise "wanted" in Craigs list or something.)

You've probably been here, but just in case:

Updated USB 2.0 Drivers Are Available in Windows 2000 Service Pack 4 (SP4)

**stroyal** · April 29th, 2011, 01:30 PM

If this is the board, it is 2GIG max.

Motherboard Specifications for the 2003 Wal*Mart Holiday Bundles - HP Customer Care (United States - English)

Asus P4 P4G533LA 184pin Desktop RAM Memory Upgrade

**kopfjaeger** · April 29th, 2011, 05:00 PM

Gents, thanks for the information you have provided thus far.

Please note, that upon installing Win2000 I always add the rollup, hotfix and SP4 service pack. But thank you very much, nonetheless for the great links. I've downloaded fresh copies of each.

Once again, in testing the USB pins for voltage, I set the digital multimeter for DIRECT CURRENT, yes? I further understand that whenever testing components, you set the original range way high, then work your way down to closer tolerances, am I correct?

Also, aside from the 5V reading I should expect from each red USB wire, what sort of reading should I expect from the other wires?

That is:

WHITE =

GREEN =

BLACK =

Where green and white are data wires, and black is ground.

ADDITIONAL SYMPTOM

I should have included this before.

When testing a new board I will often use a set of USB-powered speakers. The DIN pin goes into the green-ringed (on most machines) SOUND OUT receptacle and the power is provided by way of a standard USB connector.

Upon first plugging the USB-powered speakers they made an unusual steady loud tone. After installing PCI-USB cards and plugging the speakers into those USB receptacles, the speakers then behaved normally, that is, without the loud steady hum, but put out sounds that were normal.

I have seen other motherboard manufacturers put out USB connectors in odd configurations, that is to say NOT R-W-G-B.

I suspect this might be partially to blame for the boards' issues. The internal (front panel to board) connector is keyed normally so there is no clue from there to tell us that this is a non-standard USB configuration. Perhaps a BIOS flash from a related but unmatching board might have messed with the USB settings?

**kopfjaeger** · April 29th, 2011, 07:33 PM

ADDENDUM-DUM:

Of COURSE you are confused, because I made a statement that, as John MacLaughlin would say was 'WRONG!'

That is one Gig.

Not one Terabyte.

I used to work for the CBO. We're used to getting our zeros mixed up.

**Chuckiechan** · April 30th, 2011, 10:19 AM

Try plugging in a flash drive to one of the ports.

**kopfjaeger** · April 30th, 2011, 04:32 PM

No normal response to a USB device plugged in to an on-board USB port. The loud, steady tone on the USB speakers tells me that the R-W-G-B might be out of sequence.

That is why I have been asking you folks whether the voltage is AC or DC, and how to test the on-board pins.

Could someone please answer those questions?

**stroyal** · April 30th, 2011, 05:18 PM

Originally Posted by kopfjaeger

No normal response to a USB device plugged in to an on-board USB port. The loud, steady tone on the USB speakers tells me that the R-W-G-B might be out of sequence.

That is why I have been asking you folks whether the voltage is AC or DC, and how to test the on-board pins.

Could someone please answer those questions?

It is DC, and it is common that front ports are wired different/wrong.
I have had to change several over the years.
Seems to me there was no exact standard for the plugs.

The port itself is standard, so you only have to change the plug that plugs into the board.

You need the boards schematic, or you have to guess. (not a good idea)

All the power, except the input to the power supply is DC in a computer.

Never measured the volts on the data cables, I'm not sure you can with a multimeter.

That's what I remember, but it has been a few years since I had to change one.

I'll see if I can find a link.

**stroyal** · April 30th, 2011, 05:40 PM

Colors are not reliable, check what color wire goes to each pin yourself.
Use the ohm meter, on your Multimeter.

USB cable schematic pinout and wiring @ pinouts.ru

USB Motherboard Cable Assembly Information

**kopfjaeger** · April 30th, 2011, 08:40 PM

THANKS!

Now we are getting somewhere!

BTW - I know there are Power Supply Unit (PSU) testers which you just plug the power jack into the PSU and plug the tester across the main board power connector (and eventually the various MOLEX connectors) and it will either give you a lit LED indicator or digital readout, along with an audible signal, showing that the unit is proper or not.

Plugging a USB into a device comes with some risk, both to the device and to the Main board itself if the power and / or ground connections are off.

I, myself, have encountered 3 different USB configurations, although the most common has been Red-White-Green-Black

Red being 5V+

White and Green being Data +/-

and Black being Ground.

I have also seen them side-by-side on board connectors and inverted (lower row reversed) with the key (blocked) pinout being on the lower right-hand corner.

But then again, I have seen another configuration that was completely different from either.

QUESTION:

Is there some sort of USB testing unit that plugs into the standard (back panel) USB receptacle, in the same or similar manner to a PSU tester?

At present, what I use normally is a USB device, such as an old webcam that is known to work but very poorly or for which I cannot find drivers. It serves as a sacrificial canary in the coalmine, but a purpose-built tester would really be handy.

**stroyal** · April 30th, 2011, 09:33 PM

I have never seen a USB tester, I have just looked at the schematic for the mother board, rang out the wires and made the proper connections. worked every time.

A power supply tested is kinda useless, if you have a multimeter.
It only tests voltage, and tells you if it is within tolerances.
the tolerances are 5% for positive, and 10% for negative.
you can figure that out that for yourself.

Edit
here is a chart, if you don't want to calculate %
Voltage Tolerance - Power Supply Voltage Tolerances

**stroyal** · April 30th, 2011, 10:39 PM

I went to Asus and downloaded a manual for a P4B533, and this is what I found.

Up is toward back.

5--------------------------10
NC
GND----------GND
LDP5---------LDP6
LDM5---------LDM6
USB+5v------USB+5v
1---------------------------6

There are several other P533 boards listed.
If you take the time maybe you can find the one that looks like yours (this one was bigger)

As well if all these boards have the same pin out, it may be what the OEM boards are also. but no guarantee.

I can't seem to preview them, so I think you have to download each one.

ASUSTeK Computer Inc. -Support- Drivers and Download

**kopfjaeger** · May 3rd, 2011, 12:18 AM

Stroyal,

Would you happen to have the URL or FTP site for that manual? I've looked and my search engine has not picked up any manual for that particular board. Nor could I find it on the corporate support site.

Could you post that URL / FTP site please?

Thanks!

**stroyal** · May 3rd, 2011, 09:52 AM

Use the link I posted above.
Use option 3, select model manually

Choose PC components, then socket 478.
Then there are 6 boards with P533 on the list

Then choose the operating system, and push confirm, and you should get a list of downloads, including the manual.