Replacing a specific part on a motherboard to fix it

[Kombalaxy]

Hello there all who are reading this. I recently was a big dummy and moved a power cable while my PC was on and it somehow shorted a certain electronic on my motherboard and im not even sure what its called or where to get a new one. I looked to see what the damage was and it was and I could see which one it was and where it was. I think this is still fixable since I have a soldering iron and a heat gun. I'll supply some images of the board and what the missing part is and what the new one I need is. If anyone could help that would absolutely amazing! 

[Guest]

Shorted... probably has more damage unseen that that. I wouldn't bet on an easy fix here.

 

What board is it? Maybe find another similar board that's inop for parts on fleabay

[mariushm]

The big component is a mosfet  or a transistor, but most likely a mosfet.  That has to be same part. 

Best way would be to use liquid flux and hot air gun to solder it in place... it's kinda difficult to solder the big pad of the mosfet with soldering iron.

 

Basically drop of flux, use solder wick to take off the current solder,  drops of flux, apply solder on the pads, drops of flux again , put mosfet on top of pads with the fresh solder , bring hot air gun to gradually warm up the mosfet chip and the pads until the solder melts and the mosfet centers itself on the pads

 

The small component is a capacitor ... should be same value as the one circled with that red ... so you could desolder that one, measure with a multimeter, then solder a ceramic capacitor with same capacitance value.

Looks like it's on a 5v rail (because usb 3 ports seem to be powered by that, i can tell by that big part with 092 written on it, which is a ressettable fuse for the usb ports, to protect motherboard in case something plugged in the usb port shorts it out ), so I'd say it's some 16-25v or higher rated ceramic capacitor, probably 4.7-10uF ( ... no idea, could be a higher value).

[Kombalaxy]

4 minutes ago, ShrimpBrime said:

Shorted... probably has more damage unseen that that. I wouldn't bet on an easy fix here.

 

What board is it? Maybe find another similar board that's inop for parts on fleabay

I looked everywhere on the board and didn't see any more burnt or broken parts of the board. here's exactly what happened. The PC was running and I moved a 6 pin PCIE express power cable out of the way and grazed that part of the board. I heard a zap and it turned off. I completely unplugged it and I turned and let it sit for a minute or two and then when I plugged it back in it would turn on but then I saw that part of the board burn hot and then just turn off. then it would turn on and stay on but with no post at all. it shows the error code double upside-down FF. I did a little work to see if I could just bridge the two open spots with some wire and I would start showing other post codes and appear to boot but then the wire would start getting red and catching on fire and before you say it, yes I know, thats really dangerous. I was outside when doing this two just to not set off any smoke alarms. Also the Board is this x99 Chinese motherboard I got for like 50 on Facebook book market place. defiantly came from ali-express. I think it I could almost get it to post with that I could ad the other ecteronic back and get it to post again. you may be very well correct though too and I apricate the helpful feedback.

[Kombalaxy]

16 minutes ago, mariushm said:

The big component is a mosfet  or a transistor, but most likely a mosfet.  That has to be same part. 

Best way would be to use liquid flux and hot air gun to solder it in place... it's kinda difficult to solder the big pad of the mosfet with soldering iron.

 

Basically drop of flux, use solder wick to take off the current solder,  drops of flux, apply solder on the pads, drops of flux again , put mosfet on top of pads with the fresh solder , bring hot air gun to gradually warm up the mosfet chip and the pads until the solder melts and the mosfet centers itself on the pads

 

The small component is a capacitor ... should be same value as the one circled with that red ... so you could desolder that one, measure with a multimeter, then solder a ceramic capacitor with same capacitance value.

Looks like it's on a 5v rail (because usb 3 ports seem to be powered by that, i can tell by that big part with 092 written on it, which is a ressettable fuse for the usb ports, to protect motherboard in case something plugged in the usb port shorts it out ), so I'd say it's some 16-25v or higher rated ceramic capacitor, probably 4.7-10uF ( ... no idea, could be a higher value).

Extremely helpful info, this is exactly what I was hopping to find out and what I was looking for, I do need to get flux but hopefully I can try and fix this thing. thank you for the help. you can read my reply from another guy to see exactly how this all happened and again thanks.

[Guest]

16 minutes ago, Kombalaxy said:

I looked everywhere on the board and didn't see any more burnt or broken parts of the board. here's exactly what happened. The PC was running and I moved a 6 pin PCIE express power cable out of the way and grazed that part of the board. I heard a zap and it turned off. I completely unplugged it and I turned and let it sit for a minute or two and then when I plugged it back in it would turn on but then I saw that part of the board burn hot and then just turn off. then it would turn on and stay on but with no post at all. it shows the error code double upside-down FF. I did a little work to see if I could just bridge the two open spots with some wire and I would start showing other post codes and appear to boot but then the wire would start getting red and catching on fire and before you say it, yes I know, thats really dangerous. I was outside when doing this two just to not set off any smoke alarms. Also the Board is this x99 Chinese motherboard I got for like 50 on Facebook book market place. defiantly came from ali-express. I think it I could almost get it to post with that I could ad the other ecteronic back and get it to post again. you may be very well correct though too and I apricate the helpful feedback.

LMAO. Oh man, toss the board in the trash now.

 

[mariushm]

12 minutes ago, ShrimpBrime said:

I did a little work to see if I could just bridge the two open spots with some wire and I would start showing other post codes and appear to boot but then the wire would start getting red and catching on fire and before you say it, yes I know, thats really dangerous.

That was stupid.

One side of that is voltage, the other is ground ... it's like the + and - of the power supply.

By placing a wire across, that wire behaved like a resistor, or like the filament of an incandescent light bulb... and the wire burned up (the filament of an incandescent bulb doesn't burn because there's inert gasses inside the bulb preventing the wolfram wire from oxidizing and breaking)

 

Don't do that again, and especially don't mess with the pads on that mosfet, don't put wires there.

 

That mosfet is like an on/off switch ... there's a  gate, a drain and a source ... when something sends a tiny bit of voltage on the gate pin (probably the pad on the left side, the pad without number near it) the mosfet turns on and there's a connection between drain and source... pins 1,2,3 should be connected together and they're one of those two, and the bottom pad is the other one.

Don't try to connect those together with wires, the result would probably other components blowing up other components on the motherboard.

You need the same kind of chip, same part number, because mosfets have various properties (rds(on), capacitance, current capability, other things), so can't put just anything there)