Question I made a tiny scratch on the motherboard, and now it doesn't boot

[HelmerFrid]

Hey guys,

I need some advice and/or thoughts.

I was about to replace my CPU cooler - I removed the back plate from the motherboard (ATX AM4) and put the chassis down on the table. Although I didn't notice that there was a screw on the table cloth. This poked on the back side of the motherboard and made a tiny little scratch. Image for reference (ImgBB link).

In hopes that it didn't do any damage, I assembled everything and powered up the computer. But unfortunately it didn't start. The fans wind up and the booting process starts, but the screen stays dark. The motherboard has LEDs (for CPU, RAM, VGA etc) that can indicate any errors during the boot process, and the one for CPU lit up.

I have disassembled everything to check on the CPU (which I didn't remove before, just changed the thermal paste) and everything seems fine - so I guess this little scratch did do some damage. Or is it possible that it could be anything else? I have tried to clear the CMOS etc, but it didn't make any difference.

Is there anything I can do to fix this, or do I need to replace the motherboard?

Thanks for any advice.

 

[Lutfij]

Welcome to the forums, newcomer!

Yeah that board's a goner, unless you can find a UV mask to repair the traces that you knocked on the underside of the motherboard though as stated initially, the exposed traces are what's causing a short.

 

[Gururu]

I have a hard time seeing that the scratch could be the cause of the problem. Exposed traces dont always cause a short. If you are worried about that some recommend clear nail polish. Is the scratch below the CPU socket?

 

[Eximo]

It is possible the board was damaged in a layer we can't see, and any superficial repair becomes moot.

Based on the timing, either it was the screw that damaged it physically, or there was still some charge in the board and the screw shorted across something delicate and damaged it that way. Or just handling it caused ESD damage (less likely, but always a possibility)

Personally, I would give another go at complete reassembly, just to be sure.

 

[HelmerFrid]

Welcome to the forums, newcomer!

Yeah that board's a goner, unless you can find a UV mask to repair the traces that you knocked on the underside of the motherboard though as stated initially, the exposed traces are what's causing a short.

Thank you!

I see. Well, it should be only that one. It might look like several scratches on the pic, but I believe it's dust. Is it any way this can be repaired?

I have a hard time seeing that the scratch could be the cause of the problem. Exposed traces dont always cause a short. If you are worried about that some recommend clear nail polish. Is the scratch below the CPU socket?

Thanks. Well, I guess it is exposed - could this in any way be the cause of the problem? Is it possible I did any more damage to it when I tried to boot? The scratch is above the CPU socket.

It is possible the board was damaged in a layer we can't see, and any superficial repair becomes moot.

Based on the timing, either it was the screw that damaged it physically, or there was still some charge in the board and the screw shorted across something delicate and damaged it that way. Or just handling it caused ESD damage (less likely, but always a possibility)

Personally, I would give another go at complete reassembly, just to be sure.

Thanks. Well, it might be, but this is the only obvious damage anyhow.
I have a hard time believing there was charge in the board. It should be over an hour since I disconnected it, and it have LED lightning that drains the PSU capacitors at least. I do use anti-static wristband and take cause, and the parts been used for about 7 months only.
If I do another reassembly, is there anything in particular I should do?

 

[SkyNetRising]

It might look like several scratches on the pic, but I believe it's dust. Is it any way this can be repaired?
I guess it is exposed - could this in any way be the cause of the problem?

Exposed trace is not a problem. Broken trace is.
Your photo doesn't have resolution high enough. Can't be sure, if it is broken or not.

To fix a broken trace, you expose copper on both sides of the break, apply flux and then bridge gap with solder.
After that apply solder mask on top of fixed trace.

 

[artk2219]

Hey guys,

I need some advice and/or thoughts.

I was about to replace my CPU cooler - I removed the back plate from the motherboard (ATX AM4) and put the chassis down on the table. Although I didn't notice that there was a screw on the table cloth. This poked on the back side of the motherboard and made a tiny little scratch. Image for reference (ImgBB link).

In hopes that it didn't to any damage, I assembled everything and powered up the computer. But unfortunately it didn't start. The fans wind up and the booting process starts, but the screen stays dark. The motherboard has LEDs (for CPU, RAM, VGA etc) that can indicate any errors during the boot process, and the one for CPU lit up.

I have disassembled everything to check on the CPU (which I didn't remove before, just changed the thermal paste) and everything seems fine - so I guess this little scratch did do some damage. Or is it possible that it could be anything else? I have tried to clear the CMOS etc, but it didn't make any difference.

Is there anything I can do to fix this, or do I need to replace the motherboard?

Thanks for any advice.

That picture actually doesn't look too bad, it doesn't look like you broke any traces, but i cant tell for sure without a closer shot. I would assemble everything outside of the case, use one stick of ram, and a cheap low power video card if you have one available (something old and not very good like a gt 710 or something), and see if i could get it to post on the bench with no case and no extra parts. Then reassemble it after everything has been validated. Do you have any other spare parts you could use for testing?

 

[Eximo]

Nothing really comes to mind. Just amazing how often going through all the steps again can correct slight mistakes that may not be immediately obvious.

 

[beyondlogic]

Hey guys,

I need some advice and/or thoughts.

I was about to replace my CPU cooler - I removed the back plate from the motherboard (ATX AM4) and put the chassis down on the table. Although I didn't notice that there was a screw on the table cloth. This poked on the back side of the motherboard and made a tiny little scratch. Image for reference (ImgBB link).

In hopes that it didn't to any damage, I assembled everything and powered up the computer. But unfortunately it didn't start. The fans wind up and the booting process starts, but the screen stays dark. The motherboard has LEDs (for CPU, RAM, VGA etc) that can indicate any errors during the boot process, and the one for CPU lit up.

I have disassembled everything to check on the CPU (which I didn't remove before, just changed the thermal paste) and everything seems fine - so I guess this little scratch did do some damage. Or is it possible that it could be anything else? I have tried to clear the CMOS etc, but it didn't make any difference.

Is there anything I can do to fix this, or do I need to replace the motherboard?

Thanks for any advice.

small bit of damage done to a trace its under the 2 big scratches. that is most likely causing the errors.

you can try putting a repair solder mask on it but if its cut off a trace completely that may have not saved it.

 

[Dark Lord of Tech]

From the looks of that trace , it's not repairable.

 

[Misgar]

I agree with @SkyNetRising. I don't think there's major damage here. It looks a pretty easy fix if you have sufficient experience.

Scrape the solder mask off the broken track, a dab of flux, wave the hot air tool over the gap, apply a spot of solder paste, hot air gun, job done.

If you can't bridge the gap with solder, lay a strand of very fine copper wire across the gap and apply more flux/solder/heat.

Check to see if the board works, then apply solder mask.

I'd hesitate to use an ordinary soldering iron with a heated metal tip, in case you "lift" the fine tracks and make things worse.

The two parallel gouges are on a ground plane and probably haven't damaged anything underneath. Fingers crossed. You won't know unless you repair the broken track.

If you lack the necessary skills or confidence, take the mobo to a workshop and get an expert technician to do the job. It shouldn't take more than 10 minutes.

I hope you're successful.