Absolute Beginner.  Motherboard Repair.  Too much to handle? - Page 1
Forum section: electronics / beginners

author: fng
author_rank: Newbie
timestamp: June 20, 2019, 07:54:51 pm
content: Hey all, I am currently building a media server and damaged my motherboard during install. Normally, I'd just buy another one - however, the board I purchased is in limited demand and the price for a replacement is monumental. Before I consider other options, I'm considering repairing the board either myself or through a professional. I have no formal instruction and no equipment. However, Id be willing to invest in soldering if the price came out to be around what I'd pay a professional to do the repair. I live in Hawaii and professionals are in limited demand. I've called around to a few repair shops and they all seem to only do repairs on mobile platforms (phones/tablets). For some reason motherboard PCB seems to scare them off. I've always wanted to learn how to repair PCB and if this project is straightforward enough, it might give me the motivation I need to invest in some introductory equipment. I've attached a picture of the damaged PCB, please let me know what your opinion is on the difficulty and feasibility of this repair, much thanks!

author: mariush
author_rank: Super Contributor
timestamp: June 20, 2019, 08:01:18 pm
content: Your first problem is : do you know what components were there?Seems like there's 4 or more components that are broken off the pads, at least two capacitors and what seems to be either resistors or tiny inductors or ferrite beads.You could go to some phone repair store and just show them the board and say "Dude, just put your soldering iron on the pads and solder components here" but if you don't have the parts or don't know what was there, the guys at the repair shops can't guess what to put there, or what to buy for you.Can you say the maker and model of your motherboard? What's so special about it? If you don't know it, take some pictures of the board and post them here, the model should be written on the board.

author: GreyWoolfe
author_rank: Unknown
timestamp: June 20, 2019, 08:05:24 pm
content: From what I can see as the picture isn't the best, is that the areas you circled have the components completely missing. Do you have them or have they disappeared? If so, and you can't get a schematic of the MB to try to figure out what the missing components are, there is scant hope of you fixing it. This is not a beginner repair even with the components. Just my 2 cents. Maybe others more knowledgeable than me will comment.

author: fng
author_rank: Newbie
timestamp: June 20, 2019, 08:07:23 pm
content: Thanks for the response mariush. The board is a Gigabyte GA-7PESH2. There is nothing special about it other than it is no longer in production. I have no idea what components would be there, are there any diagram libraries that show this type of information?

author: fng
author_rank: Newbie
timestamp: June 20, 2019, 08:08:44 pm
content: GreyWoolfe, I do not have the components or access to a MB schematic. Thank you for your response and information.

author: 0xdeadbeef
author_rank: Super Contributor
timestamp: June 20, 2019, 08:19:35 pm
content: The SMD device there is a NXP PCA9517AD "level translating I2C-bus repeater". Since the upper both pins are VCC(A) and VCC(B), chances are that the two small capacitors above the IC are just bypass capacitors (100nF or something like that).

author: fng
author_rank: Newbie
timestamp: June 20, 2019, 08:24:31 pm
content: I've taken a few more pictures. I apologize for the quality, the motherboard components are small and I only have an older iphone for pictures.The first image (dmg1.png) shows the damage up close on the left most circled original image, and the second image (similar.png) shows a component that appears to be exactly what used to be on the damaged portion.EDIT: The middle damage (on the original image) appears to be the same component as the black connectors on the dmg1.png image and the right most circled damage on the original image appears to be a much smaller version of the similar.png component.

author: fng
author_rank: Newbie
timestamp: June 20, 2019, 10:00:32 pm
content: Quote from: 0xdeadbeef on June 20, 2019, 08:19:35 pmDoes this still hold true with the new pictures taken? Is it possible a local repair shop have capacitors that might fix this issue or should I look deeper into this?

author: 0xdeadbeef
author_rank: Super Contributor
timestamp: June 20, 2019, 10:17:53 pm
content: Your main problem is that there is also a larger capacitor missing (probably a few µF) and at least two resistors with totally unknown values.These could be I2C pullups with a few kOhm or series resistors with a few dozen Ohm or something totally unrelated to the I2C interface.

author: Jwillis
author_rank: Super Contributor
timestamp: June 20, 2019, 10:37:17 pm
content: Replacing a few SMD resistors and capacitors is not hard if you have a steady hand .A basic soldering iron is adequate.Try searching other forums for people that have the same board and see if they can give you a few hi rez photos.At least you would find out the type of component .If your lucky maybe someone may have one they could take a few measurements on .Couldn't hurt.

author: fng
author_rank: Newbie
timestamp: June 20, 2019, 11:26:13 pm
content: Jwillis, I'm fairly confident that I have located other components on the board are the same as the ones that were damaged. I tried explaining this in an earlier post but must have done a poor job. The structure of the damaged components look very similar to others found near or elsewhere on the motherboard. How would I go about checking what type of component they are?

author: james_s
author_rank: Super Contributor
timestamp: June 21, 2019, 12:23:30 am
content: If you were already an experienced electronics hobbyist and proficient at soldering I'd say give it a go. If you are starting from zero though I recommend sending it to someone experienced in reworking complex modern PCBs.

author: magic
author_rank: Super Contributor
timestamp: June 21, 2019, 05:27:27 am
content: Quote from: fng on June 20, 2019, 11:26:13 pmYou haven'tI mean, the brown ones are capacitors, the black ones are resistors. That's well known and there is indeed tens of each on the board.But they come in different values of resistance/capacitance and neither you nor us really know for sure what exactly was used in these particular 4 places.It would be helpful to have a picture of a good motherboard to know for sure which were R and which were C.Other than that, you may need a DMM with continuity test to figure out where they are connected. This could offer a clue about their purpose. Or see if some connections to those parts are visible on the board, but it's a multilayer board so they may be hidden inside and you won't find them.I second 0xdeadbeef wrt the leftmost/rightmost part. They are likely power supply capacitors and not very critical in value. But the ones in the middle are complete mystery.

author: perieanuo
author_rank: Frequent Contributor
timestamp: June 21, 2019, 07:30:15 am
content: Hi,My advice is to ask someone with that mobo to take e highres picture or maybe measure the non-capacitive components.For the capacitors, you have posts that already show you the way.Or find the schematic for resistors or inductor values.Replacing is not hard, put smd or th components, smd recommended if you solder within 5 secsBon courage!Envoyé de mon iPad en utilisant Tapatalk

author: magic
author_rank: Super Contributor
timestamp: June 21, 2019, 07:35:35 am
content: To be honest, I would leave soldering to somebody who has done it before or at least practice it first on some junk PCB.So far the damage is rather benign (and it's possible the board could even work as-is with minor functionality loss), no need to make it worse by putting solder blobs on nearby components or lifting tracks by accidentParticularly de-soldering SMD passives in the event that something goes wrong can be risky without experience.

author: Electro Detective
author_rank: Super Contributor
timestamp: June 21, 2019, 09:48:38 am
content: Ebay for another moboand or advertise for someone local who repairs electronics, and offer cashForget about phone repairers, they're hooked to microscopes, exclusively servicing two brands of phones for easy cashswapping out broken screens, solder re-flows and flogging overpriced phone covers and accessories.Gamer repairers are a better group to deal with afaik, and up for some alternative action.A schematic and parts list for that mobo may get it fixed fast/erEmail Gigabyte and ask nicely, you may get lucky, but don't hold your breath..

author: Siwastaja
author_rank: Super Contributor
timestamp: June 21, 2019, 09:57:19 am
content: You can try your luck with the capacitors, like the larger ones replace with 1µF 16V X7R and the smaller ones replace with 100nF 16V X7R. It's quite likely they are just power supply bypassing. Itcouldeven work without!The resistor values are a bit trickier. Try to trace, with a beeping multimeter, if one end of them goes into a Vcc pin of any nearby IC. If it does, it's likely a pullup resistor: put a 4.7kOhm there and it's likely to work. But if they are not pullups, it would be harder to guess.Get some "learn to solder SMD" kits from Ebay or so to train. OTOH, that area seems quite easy, what I mean is that it's unlikely you do a lot of extra damage.If you have difficulties to make the solder melt and flow properly, preheat the board. Motherboards have multiple copper layers inside which soak up the heat and makes soldering more difficult. Put the whole board in an oven at about 80-90 degC (no more than about 120 degC, be careful), then solder while it's still hot. A controllable hotplate is the best but you probably don't have one.If you are unsure what component sizes they are, order a few common sizes: 0402, 0603 and 0805, to see how they look like in real life.

author: larsdenmark
author_rank: Regular Contributor
timestamp: June 21, 2019, 11:03:56 am
content: This will be a difficult fix. In order to see how missing components are soldered see Louis Rossmann's YouTube channel. Note he is repairing Mac motherboard and (probably) can't help you. Here is a link to one of his videos:Note that he solders using a microscope that probably costs more than your motherboard.You may be able to get help on a Gigabyte forum about the types and values of the missing components. If that doesn't work you can find boards on Ebay that are "for parts only". Check with the seller that the parts you need are actually on the board before purchasing.A warning: You can't simply assume that a pad that doesn't have something attached should be fixed. Sometimes boards ship with components missing on purpose so you can't simply guess what parts of your board must be fixed and with what.

author: plurn
author_rank: Regular Contributor
timestamp: June 21, 2019, 12:38:52 pm
content: Hi res image of the top of the board here - click on the image then mouseover to zoom in:https://parts.metservers.com/GIGABYTE-Server-Motherboard-Fully-Loaded-with-2xE5-2667V2-3.5GHz-8Cores-CPU-256GB-RAM-IO-PlateThis image is for reference about what I am going to talk about.Since it is a dual cpu motherboard you might be able to look at a different section of the motherboard with the same function as your damaged area to find a similar layout of components. Then you could try and measure the components in the equivalent area to find the values of replacement components that you need.Not sure but your first image seems to be of the bottom side of the board, at the bottom edge of the board near the cpu0 (lower cpu on the board) and near its ram slots DDR3_P0_D1. Correct me if I am wrong.So if I am right, the equivalent area for the other cpu would be bottom side of the board near the ram slots where COM1 serial port is. So inspect that area to see if you can find a similar pattern of components to your damaged area. Then if you have the tools* (or you take it to a repairer who does) you could measure the components and then purchase replacements.Otherwise, there is currently a damaged board on ebay for US$99.99 (or make offer) that you could take a gamble on purchasing - it might have intact components in the area you are interested in. That might be throwing good money after bad though:https://www.ebay.com/itm/GA-7PESH2-GIGABYTE-Intel-Rev1-0-LGA2011-E-ATX-Motherboard-AS-IS-FOR-PARTS-/123738729773#viTabs_0Due to the high risk of not being able to fix something like this, I would not want to spend any money on it other than the small cost of replacement components, and perhaps some tools that I am likely to reuse (eg soldering tools, LCR meter). Spending $100 on a damaged board on ebay sounds like a waste of money.Good luck.* tools for measuring - you might be able to measure the resistors with a multimeter. For the capacitors a multimeter might work but many of them can't measure low values. It is worth a try though. An LCR meter should be able to measure the components but they can be quite expensive. A good value one is a DER EE DE-5000 but it would be expensive to get this if you only use it once. If you don't even have a multimeter then that is worth having. Perhaps someone can advise on a good value one that can measure resistors and low value capacitors to help with this project.Actually maybe one of these $7 component testers could do the job of measuring?"EEVblog #1020 - Is A $7 LCR / Component Tester Any Good?"

author: bitwelder
author_rank: Super Contributor
timestamp: June 21, 2019, 02:38:39 pm
content: One option regarding places where to repair the board (for cheap) could be a friendly hackerspace, if you happen to have one sufficiently near. At a quick google search there seem to be several of them in the Hawaii.An added benefit is that the local resident hobbyists/experts can help you in diagnosing the fault, using the necessary equipment, and perhaps they can also provide some replacement parts, if they are not too uncommon.

author: fng
author_rank: Newbie
timestamp: June 21, 2019, 08:40:02 pm
content: Quote from: james_s on June 21, 2019, 12:23:30 amThanks, although I am definitely interested in PCB repair, I will work on finding a different project to start on.Quote from: magic on June 21, 2019, 05:27:27 amThank you for the honest reply. I'll look into finding more information and/or pictures regarding the motherboardQuote from: perieanuo on June 21, 2019, 07:30:15 amThanks for the response @perieanuo! I have asked gigabyte for the schematics for the board (not holding my breath) and am looking to find some high res versions of the mobo soon.Quote from: magic on June 21, 2019, 07:35:35 amI appreciate the honest feedback, I will find a different project to start soldering on.Quote from: Electro Detective on June 21, 2019, 09:48:38 amInteresting, I will contact local video game repairers and see if they can tolerate the threat level of this mobo haha! I contactact gigabyte and will see about the schematics. Thanks for the info!Quote from: larsdenmark on June 21, 2019, 11:03:56 amThanks for the video! I will watch in awe at my lack of skills and equipment. I might look to find a parts board as well.Quote from: plurn on June 21, 2019, 12:38:52 pmYou are correct about the location of the damage (CPU0 near DDR3_P0_D1).I'll investigate the area you mentioned and purchase a cheap LCR. I'm looking at the followinghttps://amzn.to/2ZxjQG6but will watch the youtube videos you recommended and might be able to save even more on the backend. Thank you so much for your information and help. I'll update you as I find out more.Quote from: bitwelder on June 21, 2019, 02:38:39 pmI didn't even know such places exist! I am now looking to joining one of these... amazing.

author: fng
author_rank: Newbie
timestamp: June 21, 2019, 08:44:29 pm
content: An update to this thread. I've found a new/working motherboard that recently went up for a decent price online that I've purchased. When it arrives I will take pictures of the affected area and update you all with LCR readings of the components of interest. Maybe we'll get to close this book at some point soon. Thanks again everyone who has helped with this.

author: Electro Detective
author_rank: Super Contributor
timestamp: June 21, 2019, 10:29:21 pm
content: Quote from: fng on June 21, 2019, 08:44:29 pmNo-O-0... !I would strongly suggest that being now 'out of the woods'don't do any LCR readings just yet, just in case mobo #2 is particular about being proddedand you may have TWO books to close'mobo sad vs mobo replacement' comparison photos posted here first may give the members a clue of the missing parts,and tips on probing the boards 'safely', if required,and in case convenient in circuit LCR tests may not always tell the full story

author: magic
author_rank: Super Contributor
timestamp: June 22, 2019, 09:19:52 am
content: Quote from: fng on June 21, 2019, 08:40:02 pmYou don't need most of it. I have soldered 0402 size SMD passives even with a bulky, mains powered unregulated iron with a fine tip mounted on it. Not saying that there is something wrong with thermal regulation or a smaller iron wouldn't be betterShort length makes it easier to manipulate the tip with precision.You need something to hold the component in place, I prefer a tiny flat screwdriver but some people use tweezers. Clean the pads of leftover solder (flux helps), put the component in place, hold it down, solder one end, solder the other end. If something goes wrong, put the iron to the side and heat both ends (add more solder if necessary), when it starts to move freely by itself and not before, wipe it off with the iron. Practice everything on a sacrificial PCBBeware that those things are tiny and just love to fall on the floor.As for size of those elements, I guess the small ones are 0402 and the big capacitor was 0805. Find definitions and measure similar items on the board if in doubt. Other candidates are 0603 and 1206.Quote from: fng on June 21, 2019, 08:40:02 pmI usually don't have the luxury of buying a second PCB to measure every component so in my experience a more useful gear is a DMM with continuity test to trace the circuit and figure out how it works what should go where. You will probably need it soon if you want to do repairs.Quote from: Electro Detective on June 21, 2019, 10:29:21 pmThere is actually a bigger problem: those capacitors would certainly need to be removed from the circuit to measure them, there is likely many more caps in parallel with them and a lot of other things so in-circuit measurement would be completely bogus.Resistorsmayneed to be removed too. For starters, I always measure resistors in both directions when in circuit. Even if the results agree, they may still be incorrect sometimes.Also, if you desolder something from a working board, better don't lose it. And if you try to measure a 0402 component by squeezing it between two probes, it's very easy to send it flying far away.

author: Electro Detective
author_rank: Super Contributor
timestamp: June 23, 2019, 12:26:54 am
content: Quote from: magic on June 22, 2019, 09:19:52 am..and let's not forget the heat thrashing/cap egg boiling those nano pitas will likely get, during the removal and re-solder 'simple' measurement snafu@new players:some things -important- may be best left to pros who do this stuff every day, familiar with such components wuth spares/equivalents in stock,and run their desoldering/soldering station at correct temperatures from 'experience'after learning the costly frustrating hard way a few times first

author: tkamiya
author_rank: Super Contributor
timestamp: June 30, 2019, 05:09:18 pm
content: Based on your description of your own skill set and equipment, I'd have to say there are more chance of causing damage to the board than successful repair. Dealing with SMD is incredibly hard without experience. You heat one side and you heat the other side. By the time side 2 melts, side 1 cools. Eventually, trace gets damaged and depending on situation, it could be game over. There is a tweezer type soldering iron for this.Then there are some 3 terminal devices on your picture. Now, the correct equipment to use is very focused hot air. (hot air workstation) How to do this correctly is more art and experience than watching a video of someone else doing it.There has to be someone who's willing to do it, provided you clearly state you will not hold them responsible if something goes wrong.By the way, I have over 40 years experience in soldering but less than a year involving SMD type. I still screw up often with SMD.