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General discussion

USB connection problems

Jun 3, 2005 3:50AM PDT

I just had to recase my PC, and since the case came with front USB ports I thought I might as well connect the up to the motherboard. However, they don't work. In fact, I think they might have destroyed my USB flash drive, so I have two questions:

1. If a USB port is incorrectly connected, can this result in some sort of power surge that could have killed off my flash drive?

2. Does anyone know the correct pin configuration for connecting USB ports to the AOpen MX64 motherboard? The manual is decidedly unhelpful. There are two rows of pins, with 3, then a space, then a fourth pin on both rows. Something like this:

o o
o o
o o
- -
o o

where o is a pin, and - is a space. I connected the wires from the USB port as follows:

VCC
-
+
[space]
Earth

Is that right?

Thanks in advance,
Adi

Discussion is locked

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You can't tell by that.
Jun 3, 2005 4:04AM PDT

This is where I'm digging for the motherboard manual. In a pinch I know that +5V is the red line, the black is the Earth or GND connection and these can be found out with a VOLTMETER. That's minimal skill levels for PC builders so do use that.

As to the + / - Data connections, you can "guess" since USB specs allow you to short or reverse these without damage.

HOWEVER!!! It's very rare to find front panel wiring to be USB 2.0 capable. If your motherboard is USB 2.0 and you don't know what cable type was used or if it's just some wires, then only use USB 1.1 devices on those ports.

Bob

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It is USB 2.0
Jun 3, 2005 4:10AM PDT

At least, the box the case came in said it was. The USB ports built into the motherboard are only USB1.1 though, which is why I was keen to connect the front ones.

I seem to remember four wires - green, white, red and black. Black, as you say, is earth and green is VCC I think, so if you say the other two (+ and -) can be reversed without damage, why has my flash drive blown? Unless it was coincidence.

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I wrote about the spec.
Jun 3, 2005 4:16AM PDT

Not reality.

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USB Interface
Jun 3, 2005 4:20AM PDT

If the motherboard is USB 1.1, then can any connected USB ports only be 1.1 as well, even if they are USB 2.0 capable? Where is the speed "controlled"?

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By two factors.
Jun 3, 2005 4:22AM PDT

1. Typical USB case wires are not suitable for USB 2.0 speed.

2. The motherboard.

Bob

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Thanks for your help
Jun 3, 2005 4:30AM PDT

Much appreciated. Don't quite know what to do now, since the manual has absolutely no mention of how to connect the wires correctly, which is why I made an educated guess from other mobo configurations.