I was trying to remove the backplate and my hand slipped and I accidentally scratched it with the screwdriver. I think there used to be a transistor here. Is this fixable? I have basic soldering skills.
Edit: This is the back of the CPU socket so I’m kind of freaking out.
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I would tend yo disagree a bit with the other comments. First of all, let’s talk about the scratch. It does not looks very deep, so most likely no damage to traces. In order to have a short you would also need to have two traces exposed and some metallic object between the two. This also look unlikely to me. I would clean the area with isopropyl alcohol, check it visually. You could also cover up the scratch with nail polish.
Then, the missing capacitor. First of, I cannot make from the picture if there was a capacitor soldered there in the first place. Sometimes there are purposfuly unpopulated components. In any case, all of the capacitors you are seeing on the backside of the CPU are decoupling capacitor. They serve no other purpose than to help stabilize the voltage versus the dynamic power draw. This means that less capacitors equals less stabilisation, but not necessarily incapacity to function. I would clean also clean it up and ensure that no metallic object touches the pads. I would probably not try to replace it, as you have no way of knowing what value the capacitor is supposed to be (usually no schematic/boardview for modern products).
It is theoretically possible to damage the CPU due to a short, but likelihood seems very low to me in this case. I would clean it up, check visually, and try to turn it on.
Upon further inspection and cleaning the traces do appear to be damaged. I think i’m calling it. I’ll have to replace it. Thank you for your help.
The traces being exposed is a non-issue, might just add clear nail polish to prevent oxidation.
If a trace is completely severed, it can be restored - often with just a solder blob bridge.
I can say with absolute certainty that there used to be a capacitor in that position, you’ll definitely want to find and reattach it or source a replacement based on a schematic / boardview.
You can use a meter to check for continuity at the endpoints of each trace to verify
Did you actually try it? The scrape looks like it only hit the mask and not the traces (though it’s not the best picture).
Based on the location I would bet that’s a decoupling/bypass cap for the cpu voltage regulator. I would bet it still works if this is the case but you might get some weird issues or instability under load (or you might get lucky and it was designed with redundancy but I don’t think so that close to the socket). This assumes no traces broke, of course
Steps to fix with a $10 multimeter and a basic fine tip soldering iron: Check traces - follow them to each end and probe in diode/continuity mode. If you place a probe on either end and it beeps you’re good. If you get a $10 jewelers loupe or usb microscope you can also visually inspect but the continuity test is better. You may have to expose some of those vias (the holes at the end), a $3 fiberglass pen will do this.
Substep - fix trace if needed. This is more challenging but not terribly hard with a bit of practice. Expose the via as described above, expose a bit of the trace (or another via/pad), and solder fine wire (32 gauge magnet wire) to either side. Apply uv mask after to protect it from breaking and shorts. Keep the wire as short as possible to avoid emi. Alternatively you can rebuild the trace with copper tape or conductive epoxy but this is much more difficult.
If the traces are fine boot and stress test. See what happens. Maybe it was part of an array and is redundant and you’re lucky. Also look on badcaps.net and see if you can get a board view, if it’s popular you might get lucky. If you’re really lucky it was never populated to begin with. If it was you’ll get the value at least and smd caps are like $1 for 20 (plus $8 shipping, oof)
If there are issues for the missing cap. Smd soldering isn’t super easy but this is probably the simplest repair in smd soldering. Reflow the pads, clean and tin the tip of the iron, hold the cap in place with tweezers, tap each side until solder flows and locks the cap in. You’ll probably need to add a touch (read: extremely small amount) of solder, just tack the sides down first and then reflow to add more solder if necessary. The board view may show it’s unpopulated, then you’re done.
If you can’t find a board view you can measure some of the other caps around. Get a $20 lcr meter or get a slightly better multimeter that can measure capacitance. Measure the caps around it. If you’re consistently getting similar values (100nf, 1uf, 4.7uf or 10uf would be common here) then you can probably go with that. If the values are wildly different you’ll have to take them out of circuit, lift one leg from the board and measure again. If you get a bunch of similar readings (like 4.7uf) it’s pretty safe to just go with that
If you’re gonna trash the board anyway might as well give repairing it a shot. It’s not as hard as it sounds. Practice on some junk boards if you’re truly new to soldering. You can also find someone who does pcb rework but unless that board is shockingly expensive it’s probably not worth the money vs replacing, at least if you live in the USA
I seriously appreciate the repair advice but I think it’s all for not. I inspected the traces under direct light and saw exposed copper along the trace. I wouldn’t be able to see it if not for the light. In any case, I can’t wait the time it would take to get it fixed. I kind of need something now. That being said, I have no intention of throwing it away. I have another AM4 CPU I could pair it with so I’ll try fixing it at some point. Hopefully soon. I’m just mad at myself for letting this happen. I should have been more careful. I do plan to invest in more soldering equipment and a multimeter.
Seeing exposed copper is fine, you just don’t want that copper to be broken. A trace that is exposed is not protected as well, but will still work
Do you really think it’s a good idea to try firing it up as is? I can get some clear nail polish. I might be willing to try if that’s your recommendation. I’ve calmed down since last night.
Edit: Is there any risk of damaging the SSD’s and GPU? I wouldn’t think so?
If you visually inspect it and it doesn’t appear the copper that is exposed is broken you’re probably okay. If the copper traces are broken the issue will be more instability/unable to post. If the traces are shorting (eg lifted from the board and touching) more damage could occur theoretically but you should be able to see this and the damage doesn’t look that extensive
I would unplug all peripherals to test. Basically minimum needs to post - psu, cpu, 1 stick of ram. It’s very unlikely that anything would break but this ensures all that stays okay and more importantly eliminates a bunch of variables all at once
I’m happy to say it works great and now that I installed the new cooler it works better than ever. Thank you for helping me overcome my doubts! Is the cooper okay being exposed though? I couldn’t find clear polish.
It’s not the end of the world but sealing it at some point is probably a good idea. Uv mask is the best option and is online even at places like amazon/ebay for like $8, often comes with a (shitty but workable uv lamp to cure it
Clear nail polish might work too but I don’t know longevity, like if it would get hard and flake off after awhile especially with heat cycling inherent to that section of the motherboard
Another cheap and easy option is kapton/polyimide tape, a roll of this is dirt cheap (unless you get a crazy amount), it’s non conductive, and it can withstand far more heat than your cpu will ever make. It’s just tape so you just stick it on there. But that’s the stuff I use to mask off sections of the board that I don’t want to get hot when I’m doing hot air rework soldering so it can easily withstand like 4-500F
Doesn’t look deep enough to have exposed or cut any traces. You’ll need someone wth soldering experience to reattach the resistor / capacitor, but it’s not super difficult. Finding the correct spec part is probably the hardest part of this
Along that same line, the best option is to give it to a professional for this kind of repair. It’ll definitely cost more than doing it yourself, but you know it’ll be done right and still be cheaper than buying a new part.
There’s a good chance it’s probably fine as is. You ripped off a decoupling cap (makes the power smoother). I wouldn’t be surprised if there are enough other decoupling caps near enough by to make up for the missing one.
i don’t think the tracks are broken, it all comes down to the price of the M/B, if you can’t replace the missing capacitor and it’s an expensive motherboard you can take some place to refit a capacitor and put some uv mask on the tracks. If it’s a cheap board, just put some tape over the aired tracks and try it if you have crashes, just replace with a new one.
Pick solder nubs on either side of the scratch that are on the same channel. You can see the channels on the board, so just trace along it and find exposed solder on either end
Amd then use a meter to check continuity on each side.
Do this for multiple traces.
But, your rule of thumb is if you cant see the copper its very likely undamaged. The scratch is white colored which means it hasn’t even gone through the protective coating yet. If you see copper then you need to worry about doing continuity tests.
Wonderful day!
I am very sorry to know that…
It looks like the SMD capacitor got removed, indeed, and though it’s possible to utterly carefully solder it, the traces must also be re-verified.
The traces may require a careful soldering, too and/or at least an oscilloscope to compare the signals and not just a basic multi-meter, since their current widths, in the place of the scratch, may affect the signal for both the ends, I believe.Sincere apologies, but I would not trust the device from now on, and would replace it. Yes, it’s another investment, but it should support you in long term with much less worries and guaranteed stability!
