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Building PC: Accidentally Made Wrong Connections and Need Some Advice

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2 replies to this topic

#1 Lxno78


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Posted 04 June 2015 - 08:32 PM

I'm new to building PCs and ended up making some wrong connections. Here are the details.


Motherboard: msi, 760GMA-P34 (FX) series [MS-7641 (v5.1)]



I had the Power Switch connected to the System Fan Pins (SYSFAN1 on the motherboard).


SYSFAN1 Pin Configuration:

Pin 1. Ground
Pin 2. Speed Control
Pin 3. "Sense" (probably sensor)
Pin 4. NC (Yes four pins even though 4 is not connected).


Four pins total.


How I had the Power Switch connected to SYSFAN1:

Power Switch Positive (+) connected to SYSFAN1 Pin 2. Speed Control.

Power Switch Ground (-) connected to SYSFAN1 Pin 1. Ground.



I had both the HDD LED and the Reset Switch connected to USB 2.0 Pins (JUSB2 on the motherboard). 


JUSB2 Pin Configuration:

Pin 1 and Pin 2. VCC
Pin 3 and Pin 4. USB0 - (for Pin 3) and USB1- (for Pin 4)
Pin 5 and Pin 6. USB0 + (for Pin 5) and USB1+ (for Pin 6)
Pin 7 and Pin 8. Ground
Pin 9. No Pin
Pin 10. NC


Nine pins total.


How I had HDD LED and Reset Switch connected to JUSB2:

HDD LED Positive (+) connected to JUSB2 Pin 1. VCC.

HDD LED Ground (-) connected to JUSB2 Pin 3. USB0 -.


Reset Switch Negative (-) connected to JUSB2 Pin 5. USB0+.

Reset Switch Positive (+) connected to JUSB2 Pin 7. Ground.


Additional Details:

1. Whilst having the Power Switch, Reset Switch, and HDD LED connected improperly (as described above) I plugged in and turned on my power supply and hit the power button a few times. The computer never started up. I did hit the Reset Switch a few times while the computer was in this state.


2. I then corrected the Power Switch connection, connecting it properly, but was unaware of the HDD LED and Reset Switch being connected improperly. I plugged in my computer and turned it on. It worked and turned on.


I never hit the reset switch while the computer was on.


3. I finally connected the HDD LED and Reset Switch to the proper pins in the proper places on the motherboard.


4. The computer turns on fine and takes me to the BIOs setup screen. I have yet to set up the BIOs so I really have no way of testing anything on the motherboard through the computer itself (as in through an operating system).



1. What damage may I have caused to the motherboard considering what I have done?

2. What damage may I have caused to things like the RAM and CPU?

3. Should I return the motherboard and start again? Should I return the other components (like the RAM and CPU)?


I really don't want to install Windows onto the system if the motherboard or other components are already  damaged.

Edited by Lxno78, 04 June 2015 - 08:38 PM.

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#2 jonuk76


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Posted 04 June 2015 - 09:07 PM

To keep it simple, I think you should just test the headers you connected wrongly - i.e. the fan header - does a case fan turn when connected to SYSFAN1? If so, no problem.  Do the front panel USB ports work when connected to the headers you were using for the LED and reset switch?  If so no problem.


I think damage to the motherboard is fairly unlikely.  I think most half decent motherboards can deal with say a short on the USB header without blowing anything permanently.  CPU or memory damage from what you did is extremely unlikely.


In the case that you were unlucky and did break something, the supplier would be within their rights to refuse an RMA on damage caused by installation errors.


#3 thisisu


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Posted 04 June 2015 - 09:20 PM

I agree with jonuk... and here's a pic!



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