Can extra USB-marked-header on MOBO be used?

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First the background:
Subject: CPU down-grade.....
to be able to capture my IDE based data.

As Paul rightly pointed out, you need a beep-speaker
to detect life at the lowest level, when building on an
undocumented MOBO.

BTW the PSU seems not as critical as I was expecting.
An old 20-pin one runs in the MOBO's 24-pin socket,
and it even ran when I forgot to plug the mid-board
4-pin lead.   It's obviously got 'parallel wiring'.

It's been running like a train for month now.

The 4 USBs are equiped:
1=bootStik for Linux; 2=USB to IDE adaptor; 3= 3Gdongle;
4=USBstik for TextToSpeech for portable device.

Now I've noticed that the MOBO has got 2 extra  

Are these already used [in parallel with the existing sockets]
or can I buy a header-socket/cable/USBsocket, and get an
extra USB ?

== TIA.

Re: Can extra USB-marked-header on MOBO be used? wrote:
Quoted text here. Click to load it

They would be separate. You can use them as
additional ports.

This is an example of one, which is "twice as much as you
need". You only need half of this one, so use the top two
or the bottom two connectors. This has two 2x5 connectors,
and you'd be using one of them.

This one is just what you need, and converts a 2x5 connector
into two available USB2 ports.

( product link shortened)

While the USB2 header pattern is 2x5, it is actually two
1x5 sections. Startech also makes a plate, with two 1x5
connectors, which can be placed on the 2x5 header. With that
one, it's easier to get the wiring put on wrong (reversed).
With that plate, you can wire up one or two connectors,
as you see fit (since the wiring installs one port at a time).

On the 1x5 section, the active pins are VCC, GND, D+, D-,
leaving room for one more pin (or key) which is not used.

Over the years, there have been alternate pinouts for USB2,
so you do have to exercise some caution when dealing
with old or obscure brands of motherboards. The ease and
availability of the above adapters, assumes relatively new
motherboards that all adhere to the most common pinout. Some
of the old 2x5 patterns, one motherboard pin is labeled "OC#",
and when that gets grounded by a modern adapter plate, it
signals "OverCurrent" and the computer shuts the ports off :-)
Humorous stuff.

This page makes reference to some of the old motherboard
variations, and it doesn't even include the "header with OC# pin".
You can rewire the header end with some effort, to make it
work with most any screwy header.


When you buy PCI USB2 cards, some of those *do* use parallel
port wiring. In some cases, there is a NEC branded 4 port
chip, but the card has 5 interfaces. And that tells you
that one of the NEC ports, goes to two of the connectors.
And sometimes, the setup sheet expects you to be a mind reader,
and figure out which one on the front plate, is common
with the internal header (I use a multimeter on ohms to figure
it out). If you use the internal port, you put tape over one
of the connectors on the plate, so nobody will use it by accident.


When a motherboard has USB3 headers, the pinout is different and
so is the slot plate. Since USB3 ports are usually in short
supply, you won't necessarily see a lot of "left over" ones
sitting on the motherboard unused. Whereas with USB2, some
chipsets have six pairs, enough for three pairs on the back
and three pairs on the motherboard surface (12 ports total).
USB3, you might see one pair on the back and a spare pair
on the motherboard surface - but that doesn't happen that
often, so the demand for these would not be that great.

USB3 uses four active pins for the USB2 interface and five
active pins for the USB3 portion, and only one of the two
portions is logically enabled at a time. By way of negotiation,
the OS decides which one is available and then uses it.
(If no USB3, then reverts to the USB2 pins.) For example, my
USB3 flash stick has nine pins, and when I plug it into
my USB2 motherboard, only four of the nine pins are electrically
connected. The stick then runs at USB2 rates, because that's
all I own :-)

"USB3SPLATE (2x10 connector) - for USB3 motherboards only"

( product link shortened)


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