Updating a component on the mainboard to resolve an issue
Updating a component on the mainboard to resolve an issue
Hey everyone, I just had a bit of a mishap while working on my PC. While it was running, I accidentally shorted an electronic component on my motherboard. I checked to see what happened and found the damage clear, including the exact part and location. I believe it’s still possible to fix it using the tools I have—like a soldering iron and a heat gun. I’ll share some photos of the board and the missing piece, along with the replacement you’ll need. Any help would be really appreciated!
The main element is either a MOSFET or a transistor, but most likely a MOSFET. They should be the same part. The best method would be to apply liquid flux and use a hot air gun for precise placement... soldering the large pad can be tricky with a regular iron. You’d just drop a bit of flux, use a solder wick to remove excess solder, add more flux, place the pads, repeat the flux drops, then position the MOSFET on top with fresh solder. Gradually heat the chip and pads with the hot air gun until the solder melts and the device settles. The tiny part is a capacitor—its value matches the one marked red. You can desolder it, check resistance with a multimeter, and replace it with a ceramic cap of the same capacitance. It seems to be on a 5V rail, as indicated by the USB 3 port labeled “092,” which is a resettable fuse for USB protection. Likely it’s a ceramic capacitor rated for 16-25V or more, probably 4.7-10µF.
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.
Very useful details, this matches exactly what I was trying to discover and what I needed. I should aim to retrieve the flux and I hope I can resolve this issue. Appreciate the assistance. You can check my response from someone else to understand the situation better, and thank you again.
This setup involves a voltage source and ground, acting like the positive and negative ends of a power supply. Inserting a wire changes its role—similar to a resistor or the filament in an incandescent bulb. The wire would heat up, similar to how the filament doesn’t burn due to inert gases preventing oxidation. Avoid repeating this action; especially avoid touching the pads on the MOSFET. It functions like an on/off switch with gate, drain, and source connections. When a small voltage is applied to the gate (likely near the left pad without a number), the MOSFET activates, creating a connection between drain and source. Connect pins 1, 2, and 3 together, and the bottom pin should connect to one of them. Don’t force wires onto these pads; doing so risks damaging other components on the motherboard. Use the correct chip with the same part number—MOSFETs vary in specs like RDS(on), capacitance, and current rating, so compatibility matters.