MotherBoard Upgrade - Connect Box Connectors to Mobo Front Panel pins


I've got an urgent question.

I've just replaced my Mobo with a new one, when trying to connect the box connectors to the mobo front panel I came across few problems.

1. Could you please explain what GND is? and what happens if I don't connect it.
after messing with the connectors I assume the GND over my case is 'white color' does it make sense?

2. Assuming GND is the white connector if for example on the pwrbutton.
I connect the pwrbutton where the GND suppose to be and the GND where the pwrbutton meant to be.
Will it do any harm? because after doing so the computer still powered up... so what are the reprecuations?

3. One more problem, i can't fit the PLED+,PLED- from my box to the mobo.
The Pled+(green color) and PLED-(white color) are found on a 3 connector pins where only the left side(green connector) and right side (white connector) are located.
therefore, I obviously cant put it in the mobo since my mobo only have a spot for 2 more pins, so at momment It's the pwrbtn or the pled and obviously i can't work without the pled.
again what are the reprecation on that one?

Thanks in advance experts.

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For the power button and reset button, there is no concern over grounding. It does not matter which way you connect them, because all that will ever happen, is when you push the button on your PC, it will connect those two pins together. If you're ever in a computer shop, you will often see people starting up a PC to test it by connecting the two pins together with the tip of a screwdriver. So there is no polarity there that matters.

For the speaker, if you hook up positive and negative backwards, nothing bad will happen, but the speaker will sound bad. For the LEDs, hooking them up backwards will cause them not to function, or possibly to burn out. (This should not be harmful, but it will potentially make them not useful to you)

As far as the question 3 goes:

You NEED a power button or you cannot turn on the PC. The PLED is a light that lets you know the PC is on, which is not terribly useful since the fans typically make more than enough noise to let you know it's on also. However, if you want to fix it, what you can do:

Find something with a sharp tip. Your 3 pin connector currently has wires on pins 1 and 3. Take the wire out of pin 3 by pressing down on the metal tab that secures it. (This is hard to explain, but suffice to say, if you take some time and poke at it, you should be able to remove the wire intact from pin 3 of the connector) Then simply slide it into pin 2 of the connector, and cut off the pin 3 portion of the connector. Alternatively, you can carefully cut the connector in half, and then slide each pin onto the connector singly. Alternatively to that, you can buy a 3 pin to 2 pin adapter to do it without any cutting. I was trying to find you a linky, but I'm striking out. I know I've seen them at Fry's Electronics before. MicroCenter is a good bet also.
GND = ground
PLED = Power LED

The white is normally refered to as the negitive wire and the color one is the positive one, and black is norminaly the ground wire.
On the LED wires the Colored one is the + and the White is the -
On the Speaker the Red is the + and the Black is the -
On the Power and Reset connectors polarity does not matter so you can connect these any way you want.

(Tip: Plug in the Speaker wire an notice which side the lettering is on, then plug in all the other wires with the lettering in the same direction)
Brian PiercePhotographerCommented:
GND is the ground or earth it normally needs to be connected for the swtich to function.
PLED+ and PLED- are the +ve and -ve connections for the power LED. If these are not connected to the correct pins and the right way around the power LED will not light when the unit is switched on.
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Elite_BigfootAuthor Commented:
I assumed GND= Groun, but my question is what could happen if I do not connect it correctly?

Could one be electrified by touching the box incase of incorrect connection?

Also you mentioned that Power button and Reset polarity does not matter, so I wonder why in the mobo-guid books they wrote perfectly clear that over the pwrbutton (2-pin connectors 1 right and 1 white) should be connected as follow:  left - pwrbtn# and right - Gnd.
However, it doesnt matter how I connect the pwrbutton connector (either placing the green to the left or right) it will stil work, but I guess it doesn't grounded so is it safe to work that way?

Don't want my kids to get electrified or something, you know...
You can only use Power and Reset connectors if you want. There is no electrical shock happens, so dont worry about that.
Elite_BigfootAuthor Commented:
Ok guys thanks for you information.

However, one more thing that I question.

After the upgrade no matter what the computer is doing the flooppy drive's led is always active(green led on) no matter If it's being used or not.

Could anyone point to the cause of this?

Could be a borken floppy?
No, LED light all green all the time on Floppy drive might wrong polarity of cable or electrical error (drive is faulty). It should light up during boot, then turn off.
Elite_BigfootAuthor Commented:
Well How could I fix this?
Check cable installation. The twisted cable should be connect to floppy and other terminal go to board. Also, you might hook up floppy onto other system see if it work properly or is it faulty drive.
Elite_BigfootAuthor Commented:
Thank you all for the help.
Just FYI, not sure if you got it, but if the floppy drive green access light is always on, it means you have the data cable on backwards. Unplug the data cable from the motherboard or floppy drive, turn it 180 degrees and plug it back in and when you boot up, the light should be on for 1-2 seconds and then turn off.

You can cut the 3 position PLED (power LED) connector from your case in half, since the center position is unused. Or, you can obtain a 2 pin motherboard to 3 pin case PLED (power LED) adapter at
Item description: Pactech: PA-2F3M06/PWR-6' 2-Pin Male to 3 pin Female Adapter, For Power LED Connector On ECS MB
Product number 3694935;jsessionid=AX-V4zr7W+CexR5KBn7mmw**.node1?site=sr:SEARCH:MAIN_RSLT_PG

Note that despite the (incorrect) product description, it is has a 3 pin male (with center pin unused) wired to a 2 pin female connector. It will allow you to connect a 2 pin PLED (power LED) motherboard header to a 3 pin case connector socket (3 pin socket with center position unused). I know this because I bought one.
In my case (pun intended) I need the opposite adapter: a 2 pin male to a 3 pin female.

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