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How can I desolder chock coil in PGA370 socket mainboard

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    How can I desolder chock coil in PGA370 socket mainboard

    I have a PGA370 socket mainboard and it seems its Toroidal Choke Coils have been burnt.



    when I power on this mainboard,CPU become get hot and keyboard bulb of Num,CAPs,SCROLL lights up but Monitor displayed black screen and no signal..

    I tried to delsolder this Toroidal Choke Coils of 3.6uH(I doubt that written symbol of 3.6microhenry is correct or not..)But It is really impossible for me to desolder Toroidal Choke Coils with 20w or 30w soldering iron..



    How can I desolder it from mainboard and Is it possible to desolder it with only 20w soldering iron?
    and Is there any electronic shop where sells Toroidal Choke Coils of 3.6uH?
    And for your information, Name of This mainboard is PYRAMID-5 and PCB NO:BA41-00143A REV:1.2 681M-35AG which is part of SAMSUNG M5317 MAGIC STATION PC.
    any reply would be appreciated..

    #2
    Re: How can I desolder chock coil in PGA370 socket mainboard

    Looks like you or someone has replaced the capacitors near the Toroids. The old caps were probably vented (bulging and leaking), causing the toroids to overheat. Replacing the toroids will not fix the no display problem. A toroid is simply copper wire wound around an iron core. They don't burn out. I've got two Abit boards with "burnt" toroids that worked fine after I replaced the bad caps.

    Does the board have on-board video or does it use an add-on video card? We need a picture of the entire board to see what the problem is.

    You need a more powerful soldering iron to properly repair motherboards. Older boards like this have thicker traces and need more heat than 2o watts. The Solder Station I use is 65 watts. a 20-watt iron is likely to give you poor solder joints.

    Comment


      #3
      Re: How can I desolder chock coil in PGA370 socket mainboard

      As we already pointed out, I have soldered solder joint of capacitor which located next to CPU socket,Because At first,I have take a closer look at all of capacitor and cannot found any bulging on any capacitor..So I doubted that black screen of no signal caused by Broken solder joint or any solder joint problem..

      I have showed this picture of chock coil to korean retro mainboard enthusiast and they said that it is rare to burnt out chock coil in mainboard, and It means that most of my mainboard's pattern which located near chock coil must have been broken and It is surely impossible to fix my mainboard..

      and below is the whole picture of my mainboard and it only supports onboard display and don't support any AGP Graphic card.




      and For your information,Blue Capacitor is LXZ v6.3 1500uF and black Capacitor which located next to 20 pin power connector is TMQ 6.3v 1500uF.
      By the way, Currently I don't have spare capacitor of any 1500uF,Is it possible to these replace 1500uF capacitor with 10v 1000uF or 6.3v 2200uF capacitor?
      Last edited by bshi02; 02-25-2021, 11:41 PM.

      Comment


        #4
        Re: How can I desolder chock coil in PGA370 socket mainboard

        The only two ways an inductor coil could fail is either if it is open circuit or there is a short between two or more turns

        With the design of that type of coil I don't see how it is possible to have a shorted turn, but if you take the heat shrink sleeving off it then you would be able to see if any turns are touching and the enamel coating is damaged, and just move them apart

        So if it does not read open circuit on your multimeter then I don't see how it can be faulty. if it does read open circuit you can almost certainly fix it anyway

        Regards your soldering iron it is too under powered - and to be quite honest a 65W 'regular' type soldering station is not going to be going to be much use for motherboard work anyway - I know because I tried and struggled with one. Get yourself a T12 soldering iron from aliexpress or similar (there are various makes but I recommend KSGER) and get a few tips but make sure you have a BC3 tip as they are best for this sort of work. Plus some flux and 60:40 leaded solder. That will make all the difference in the world, and the 'impossible' will because easy.

        There is one other option - if you have a hot air gun, then heat that area up until it is hot but not enough to melt the solder, then before it cools down use your 20W iron and add some leaded solder, then you should be able to desolder and pull the inductor out. But really I don't think it is going to be faulty. Does it read open circuit?


        Also you say it only supports on board display, this is incorrect - it will work with a PCI graphics card so I would try that. PCs did use PCI graphics cards for several years before AGP even existed. Actually even before PCI they used VLB and before that ISA (and before that I don't know).

        Do you get any beeps on the motherboard speaker (did you attach one)



        Rich
        Last edited by dicky96; 02-26-2021, 04:32 AM.
        Follow me on YouTube
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          #5
          Re: How can I desolder chock coil in PGA370 socket mainboard

          I took off shrink sleeving and I took the picture of below screenshot.






          And I also made a youtube videoclip which display specific symptoms
          of mainboard
          youtube videoclip
          I did continuity test with multimeter and it seems that it is not open circuit between two solder joint of inductor coil.(03:30)
          and It is impossible for me to hear any beep sound during booting test.

          Frankly speaking,I solely depend on my mother for so much economically as I'm still looking for a job..
          But My mother really hate me to do soldering in house because she strongly believe the myth that Lead fumes cause lung cancer So I always have done soldering when my mom was sleeping in bed or when She was out.

          I saw T12 soldering iron which was sold in aliexpress. But It would be impossible for me secretly receive it and hiding it from the eyes of mother.

          https://www.aliexpress.com/item/1005001817861092.html
          Last edited by bshi02; 02-26-2021, 10:20 AM.

          Comment


            #6
            Re: How can I desolder chock coil in PGA370 socket mainboard

            OK that coil looks fine. Just out of interest what voltage do you read at the coil with your multimeter

            Ahh bless your mother ,but I am sure you know, soldering does not raise the temperature of the solder high enough to vaporise it - so you can not breath in 'lead' even from leaded solder, the fumes are caused by the flux, and though it can be an irritant, I never suffered any health problems from soldering, and I've been doing it 48 years now! And fume extractors were not a 'thing' when I worked in large commercial workshops with 100+ repair engineers back in the 80s and 90s.

            Even now I just use a PC fan to blow the fumes away from my face when soldering under the microscope or desk magnifier.

            Regards sneaking a T12 in the post - this sort of situation is what friends are for

            Now let's try to fix your motherboard. You say the CPU gets hot (I saw your video - please tell me you are NOT running that CPU without a heatsink!!!) If you are you need to put a heatsink on that right away and hope to god you haven't toasted it already!

            Now once you have a heat sink on the CPU here are a few basic checks:

            1. On your pics I don't see a CMOS battery. You need to fit one. Once fitted measure the voltage on the top of the CMOS battery to ground. What voltage do you see?

            2. With the motherboard powered up, When you press CAPS LOCK on your keyboard, does the CAPS LOCK LED turn on and off ?

            3. You say you can't hear any BIOS beeps? Remove the RAM and power it up without RAM fitted - does it beep now? You do have a speaker/buzzer yes?

            4. Do you know for sure if the CPU is good? Is it tested and working in another motherboard?

            5. Do you know the BIOS revision for your motherboard, and what model is the CPU?


            The answers to those should be a good starting point.

            Rich
            Last edited by dicky96; 02-26-2021, 11:03 AM.
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              #7
              Re: How can I desolder chock coil in PGA370 socket mainboard

              After the above questions above I would look into the capacitors.
              It looks like the sticky gunk under the coil came from the capacitors.
              Because in your latest pictures I can see it also under the capacitors.
              P.S: If the capacitors are bad the coil could get very hot!
              "The one who says it cannot be done should never interrupt the one who is doing it."

              Comment


                #8
                Re: How can I desolder chock coil in PGA370 socket mainboard

                Originally posted by dicky96 View Post
                OK that coil looks fine. Just out of interest what voltage do you read at the coil with your multimeter

                Ahh bless your mother ,but I am sure you know, soldering does not raise the temperature of the solder high enough to vaporise it - so you can not breath in 'lead' even from leaded solder, the fumes are caused by the flux, and though it can be an irritant, I never suffered any health problems from soldering, and I've been doing it 48 years now! And fume extractors were not a 'thing' when I worked in large commercial workshops with 100+ repair engineers back in the 80s and 90s.

                Even now I just use a PC fan to blow the fumes away from my face when soldering under the microscope or desk magnifier.

                Regards sneaking a T12 in the post - this sort of situation is what friends are for

                Now let's try to fix your motherboard. You say the CPU gets hot (I saw your video - please tell me you are NOT running that CPU without a heatsink!!!) If you are you need to put a heatsink on that right away and hope to god you haven't toasted it already!

                Now once you have a heat sink on the CPU here are a few basic checks:

                1. On your pics I don't see a CMOS battery. You need to fit one. Once fitted measure the voltage on the top of the CMOS battery to ground. What voltage do you see?

                2. With the motherboard powered up, When you press CAPS LOCK on your keyboard, does the CAPS LOCK LED turn on and off ?

                3. You say you can't hear any BIOS beeps? Remove the RAM and power it up without RAM fitted - does it beep now? You do have a speaker/buzzer yes?

                4. Do you know for sure if the CPU is good? Is it tested and working in another motherboard?

                5. Do you know the BIOS revision for your motherboard, and what model is the CPU?


                The answers to those should be a good starting point.

                Rich
                Thank you very much for your detailed reply!
                I power on mainboard and did voltage test on solder joint of chock coil with digital multimeter and it display 14.4mV.

                I didn't even think that you are top-class Electronics Engineers who has nearly 50 years experience. Frankly speaking I have been totally crazy for video game almost 20 years..I have neglected to get a job and put my whole life into video games.. It awfully ruined my 20s and 30s and totally destroyed any relationship with my friends..It give me only fundamental level of japanese language skill.I am really regretful for being enthusiastic to video games.
                Currently I try to get a job of Computer Repair Service center in korea and want to acquire a practical skill of repairing PSU or mainbaord, I really want to be top-class Electronics Engineers like you.
                Anyway, I think If I can power off mainboard within 30 seconds or 1 minute as soon as I power it on, It is all right for CPU even without a heatsink. Because some Capacitor in pyramid-5 mainboard is very adjacent to CPU and I think there is danger of breaking capacitor if nose pliers miss when I strongly push the latch of heatsink with nose pliers.

                1.When motherboard powered up, It display 3.08-3.09v whenever I did voltage test on top of CMOS battery and solder joint of CMOS battery holder with multimeter.

                2.When motherboard powered up, CAPS LOCK LED don't works whenever I press CAPS LOCK key several times.

                3.I cannot hear any BIOS beeps without any RAM in DIMM slots.

                4.I confirm this CPU surely works on other mainboard(6BX67) and this CPU is
                Intel Celeron 366Mhz.

                5.I Don't know the BIOS revision for my mainboard(Pyramid-5). As far as I know This mainboard was exclusive for Samsung PC,and Now It is impossible to search for any driver or bios for this mainboard on the website.
                Last edited by bshi02; 02-26-2021, 11:05 PM.

                Comment


                  #9
                  Re: How can I desolder chock coil in PGA370 socket mainboard

                  Originally posted by Per Hansson View Post
                  After the above questions above I would look into the capacitors.
                  It looks like the sticky gunk under the coil came from the capacitors.
                  Because in your latest pictures I can see it also under the capacitors.
                  P.S: If the capacitors are bad the coil could get very hot!
                  I take a close look at blue capacitors and It seems that there is trace of sticky gunk which came from capacitor.
                  I think this capacitor need to be replaced.
                  By the way Is it alright to replace this 6.3v 1500uf with 10v 1200uf or 2200uf capacitor?

                  Comment


                    #10
                    Re: How can I desolder chock coil in PGA370 socket mainboard

                    You could probably get away with replacing this capacitor with either 1200uF or 2200uF.
                    But they need to be low ESR capacitors, otherwise it will not work.
                    Below is the datasheet of the original capacitor, the ESR is 0.052ohm at 100kHz
                    Your replacement capacitors should match that or be lower to work well, I would recommend Panasonic FC or FS
                    P.S: You need a better soldering iron to replace these too!

                    https://cdn.badcaps-static.com/pdfs/...1347f479b3.pdf
                    Last edited by Per Hansson; 02-27-2021, 02:38 AM.
                    "The one who says it cannot be done should never interrupt the one who is doing it."

                    Comment


                      #11
                      Re: How can I desolder chock coil in PGA370 socket mainboard

                      Hi bshi02
                      Thanks for the answers - and the compliments

                      No really I have decades of electronics repair experience but only about 18 months at motherboard repair. We can all learn more whatever our age so continue on your journey to learn the skill to want. I ask a lot of questions of the other guys here myself.

                      Now it may be a language translation thing but you really didn't do as I asked.

                      1. You DO need to fit a CMOS battery before you go any further. This is basic simple thing and you should not ignore it.

                      2. Really you DO need to fit a heatsink to the CPU. I would test the CPU again in your known good board to make sure it is still OK then put it back in this board.

                      Personally a lot of time when diagnosing faulty board, I just put some heatsink compound on the CPU and then rest a CPU cooler on top of it (so the compound sticks it to the CPU. I have some old CPU heatsink with a flat base and side mounted fan for this use for this purpose. I'm pretty sure it came off a P4 Socket 478 as these type of heatsink don't have any mounting legs/holes/arms, they are quite hefty and it does the job for me (though again others here may shoot me down for my cavalier approach to cooling!) Also bear in mind, probably not for an old board like this, but for newer motherboards, they will power up and shut down again if you don't have a working fan connected to the CPU FAN connector. You could waste a lot of time because of that.

                      3. You say you measure some 14mV on the choke coil. Are you measuring with one lead of your multimeter connected to ground (chassis) and the other lead on the coil, and are you using DC volts range? If not, try again please.

                      Yes like Per Hansson says - those capacitors look like they 'lost their snot' and definitely need replacing.

                      From the keyboard/CAPS lock test, and the lack of beeps with/without RAM, it is pretty clear this motherboard is not booting at all

                      Now just a little friendly advice, an please take this the way it is meant - You will find that folks here will do all they can to help you with repairs, but if you don't or can't follow the instructions they give you then you are going to find they will lose interest in helping you pretty quick. OK.

                      To continue with this firstly you need to do as I asked regards CPU heatsink and CMOS battery and you are going to need to invest in some more kit:

                      So you need now to consider the investment needed and decide if this is a skill you really want to learn. I can tell you it is very worthwhile skill and can also make you some good money in time, but you must appreciate you need to invest time and some money yourself to begin. You don't need expensive kit to start with, but continue you are going to need the following:

                      A. Replacement Capacitors of the type recommended by Per Hansson

                      B. A Decent Soldering Station - Would still recommend T12, and you need some decent tips to go with it. BC3 is good for the capacitors. Personally I use the following three tips almost exclusively.
                      BC1 for fine soldering
                      BC2M for 'drag soldering'. You can google that if you don't know what it means
                      BC3 for things like capacitors
                      Also I honestly recommend this type of T12 soldering handle
                      https://www.aliexpress.com/item/4000...archweb201603_

                      In my opinion they are much easier to learn this type of soldering with, as your hand is much closer to the tip so you can control it better. I used to use this type of soldering iron (I still have the ZD-916 station)
                      https://www.aliexpress.com/item/1005...archweb201603_

                      But having used the T12 with aluminium handle I don't see me ever going back to the old type of soldering irons.

                      C: 60:40 Leaded Solder

                      D: Desolder Braid

                      E: Flux. I use this stuff now, after being recommended here and it is really excellent
                      https://www.aliexpress.com/item/3278...archweb201603_

                      F: Desoldering needles
                      https://www.aliexpress.com/item/1005...archweb201603_

                      G: Really you should also get a hot air station - even one of the cheap ones is good enough for most work
                      https://www.aliexpress.com/item/1005...archweb201603_

                      I used to have, and still have, the same hot air station - it allowed me to do almost everything (except BGA) and is perfectly good for learning. Later if you progress you will end up upgrading, as I did, but for now it is good enough. I can tell you now, without hot air you are going to seriously struggle to remove the old solder from the holes after removing the capacitors.

                      With hot air, you can just push the needles through the holes, then use braid and flux for final cleaning


                      So now you have to decide, is this an investment you want to make? If so than you will find a lot of guidance and help. Without this, IMHO, you really can't do this sort of work.

                      Rich
                      Last edited by dicky96; 02-27-2021, 04:45 AM. Reason: fixed links
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                        #12
                        Re: How can I desolder chock coil in PGA370 socket mainboard

                        you need to put a fan on the cpu

                        Comment


                          #13
                          Re: How can I desolder chock coil in PGA370 socket mainboard

                          I'm sorry for making a mistake in measuring choke coil.I don't have enough practical eletronic knowledge..So I thought that Any choke coil on the mainboard has both solder joint of possitive and negative.. I did voltage test on solder joint of chock coil and chassis of ps/2 port and it display 1.96-2.00v.
                          In the same way,I also did voltage test on small chock coil which located next to 20 pin power connector and It display 5.02v.
                          And I always test CPU in other normal working mainboard before I test problematic mainboard in order to confirm whether CPU really works or not.

                          Although it is always time consuming for me,I can understood most of your words,but It is always extremely hard for me to write what I thought in English, especially writting long sentence. I'm sorry it is my mistake to omit "fitting CR2032 Lithium battery" in my previous writting.
                          I surely did voltage test with fitting a CR2032 Lithium battery into CMOS battery holder of mainboard and it displayed 3.08-3.09v.

                          Thank you very much for your advice of choosing soldering tools.
                          Several years ago, When at first I was interested in repairing mainboard, There was no one who kindly advise me and even I have experience of mocked by clerk of eletronic tools store in korea and my parents explicitly obstructed my repairing because They thought that fiddling with disassembled PCB and especially soldering directly onto PCB and powering on it would cause fires in house someday, and lead fume is very harmful to their health.

                          And I have asked for some question about repairing electronics or mainboard to Korean experts(Now I think they are self-proclaimed experts not genuine experts) But They give only superficial and worthless answer. and They always thoroughly keep repairing process a secret and make every effort to advertise their repairing business all over korean retro Enthusiasts community. There have been no one in korea who give me detailed knowledge of advice like you.

                          I will persuade my mother to admit me to get into the field of repairing electronics or mainboard.

                          By the way If I get a permit from my mother I plan to buy SET8 T12 station of below link and change default tip to BC1,BCM2,BC3. Is it enough for soldering iron to start with my repairing?
                          https://www.aliexpress.com/item/32803295956.html
                          Last edited by bshi02; 02-27-2021, 08:13 AM.

                          Comment


                            #14
                            Re: How can I desolder chock coil in PGA370 socket mainboard

                            Yes it is enough. I much prefer the aluminium handle but that is personal preference - I am sure some folks here will agree with me and some will not. Regardless of whatever handle the T12 will have the same soldering power, it is more about the balance of how it feels in the hand.

                            There are various handles you can use with the T12 and sometimes you find them for sale with the handle you want. Anyway these are interchangeable and you can upgrade it later

                            https://www.aliexpress.com/item/3300...archweb201603_

                            I have the all black KSGER one, but the blue/black one also has the advantage of holding the iron much nearer the tip, and the quick change of tips, and it is almost the same price as the type on the listing you posted - so have a look around. By the way the aluminium handles do not get hot when in use, they are very comfortable!

                            Did you know that T12 soldering irons have the heater integrated into each tip? This makes changing tips very easy (quick change is easier on the aluminium handles which is another reason I like it) and the integrated heater it makes the iron much more efficient at transferring heat into the solder joint, which is why a 70W T12 over-powers and out-peforms a regular 65W soldering station by so much.

                            Do get the flux, some 60:40 leaded solder, desolder braid and the desoldering needles. They will not cost very much, and you really will need them.

                            There is a soldering techniques section on the forum, but my basic method is to get a big blob of solder on the BC3 tip (which is quite large) and then you can usually get to heat both leads of the capacitor at the same time, and pull the capacitor out with your hand. if the leads are too far apart, heat one lead at a time and rock the capacitor side to side to pull that leg partially out from the board, then do the other leg, then come back to the first one and pull it a little further out.. and so on until the capacitor removes from the board. You should keep a large blob of solder on your iron tip while you do this.

                            Oh you are going to need a soldering iron stand with wire wool or wet foam to keep your iron tip clean, as you will be wiping excess solder off it a lot while desoldering. There are no stands specifically for the T12 (or they are expensive) so I use this type for my aluminium handle and it works well.
                            https://www.antex.co.uk/products/spa...ies/st4-stand/

                            If you ask in the soldering techniques section here someone will advise what stand is best to get for your soldering iron.

                            Once you got the capacitors out, try cleaning out the holes with flux and braid. you probably won't be able to do the ones on the ground plane. this is where the desoldering needles are going to be needed. Don't bother with desoldering pumps - I find the hand held desoldering pumps to be almost useless at cleaning out holes, but the recoil when you press the spring release is great for damaging pads on the board.

                            At this point you will also find out whether you needed a hot air station or not.

                            I actually use a mix of hot air and an electric vacuum pump desoldering tool to clear the holes now, this one:
                            https://www.aliexpress.com/item/3298...archweb201603_

                            With this one:
                            https://www.aliexpress.com/item/3292...archweb201603_


                            But that costs more money, and you can do it with the basic tools I suggested (possibly needing hot air with the needles) and a bit of care and patience. That is how I started. Sure it is time consuming, and if you start doing a lot of this sort of work get the vacuum desoldering tool. And I still have to use hot air to heat the ground planes even with the vacuum desoldering tool! You will see me working with hot air wand in the left hand and the desoldering vacuum in the other at the same time - this combination works wonders sucking out holes though lol!

                            Really to go into detail further, ask for advice on desoldering capacitors in the relevant forum section, as a lot of folk won't be reading in this section

                            https://www.badcaps.net/forum/forumdisplay.php?f=33

                            Ask there what is the minimum amount equipment you will need to buy, I am sure you will get a second opinion. And a third and fourth...........

                            Anyway - good luck
                            Last edited by dicky96; 02-27-2021, 09:37 AM. Reason: more info
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                              #15
                              Re: How can I desolder chock coil in PGA370 socket mainboard

                              Maybe a stupid question, but have you checked the jumper configuration in the mainboard (CPU multiplier, FSB, Vcore....)

                              Comment


                                #16
                                Re: How can I desolder chock coil in PGA370 socket mainboard

                                Originally posted by bshi02 View Post
                                But My mother really hate me to do soldering in house because she strongly believe the myth that Lead fumes cause lung cancer So I always have done soldering when my mom was sleeping in bed or when She was out.
                                Originally posted by dicky96 View Post
                                Ahh bless your mother ,but I am sure you know, soldering does not raise the temperature of the solder high enough to vaporise it - so you can not breath in 'lead' even from leaded solder, the fumes are caused by the flux, and though it can be an irritant, I never suffered any health problems from soldering, and I've been doing it 48 years now!
                                Originally posted by bshi02 View Post
                                Several years ago, When at first I was interested in repairing mainboard, There was no one who kindly advise me and even I have experience of mocked by clerk of eletronic tools store in korea and my parents explicitly obstructed my repairing because They thought that fiddling with disassembled PCB and especially soldering directly onto PCB and powering on it would cause fires in house someday, and lead fume is very harmful to their health.
                                yea... lead has a melting point of 327.46°C and a boiling point of 1749°C. the temperature used in soldering is between 300-400°C and its not hot enough to vaporise lead, so sorry to say, u are better educated than your parents in that regard.
                                Originally posted by bshi02 View Post
                                Frankly speaking I have been totally crazy for video game almost 20 years..I have neglected to get a job and put my whole life into video games.. It awfully ruined my 20s and 30s and totally destroyed any relationship with my friends..It give me only fundamental level of japanese language skill.I am really regretful for being enthusiastic to video games.
                                hahaha! dont worry, im sure many of us here can relate to that too! keke! however, u are too pessimistic. do note that it only destroyed your relationship with your real-world friends. i have plenty of online friends from my video games and on other places on the internet like here.

                                as for girlfriends, girlfriends are overrated. many of us here prefer the freedom of being single. girlfriends take up too much time, effort, energy and money. god knows how many girls i rejected and turned away because i preferred the freedom of being single.
                                Originally posted by bshi02 View Post
                                Several years ago, When at first I was interested in repairing mainboard, There was no one who kindly advise me and even I have experience of mocked by clerk of eletronic tools store in korea and my parents explicitly obstructed my repairing because They thought that fiddling with disassembled PCB and especially soldering directly onto PCB and powering on it would cause fires in house someday, and lead fume is very harmful to their health.
                                Originally posted by bshi02 View Post
                                Currently I try to get a job of Computer Repair Service center in korea and want to acquire a practical skill of repairing PSU or mainbaord, I really want to be top-class Electronics Engineers like you.
                                repairing computers is not a skill u learn or pick up in school. u have to learn it by experience in the real world by finding broken computers and then fixing them. its what dicky96, momaka and many others here do. school can only teach u very basic things used in computers like electrical circuits, logic circuits, power supply circuits etc. the rest is you learning by experience.

                                while its a nice job with decent pay, this job wont make u so rich that u can buy an apartment in the gangnam district of seoul unless u wanna go into data recovery. some companies that dabble in data recovery with clean room labs can bill customers thousands of dollars or millions of korean won. so if u wanna be a millionaire in korean won and make your first million easily, u can try going into data recovery but u also have to spend money first to pay for a clean room lab which can be costly also.

                                otherwise, learning data recovery using software like gnu ddrescue for linux, mhdd, testdisk etc. is the way to go. typically u can bill clients a few hundred dollars or a few hundred thousand korean won for their data back depending on how many gigabytes and terabytes it was that u managed to recover.
                                Originally posted by bshi02 View Post
                                It give me only fundamental level of japanese language skill.
                                Originally posted by bshi02 View Post
                                It is always extremely hard for me to write what I thought in English, especially writting long sentence.
                                well, thats another language for you to learn: english. its very easy to pick up, dont worry. although, i've never been to korea or japan before but from what i heard from people who have been there, they said that people tend to run away from them if they speak english to the koreans and japanese. (no racism intended) so thats something u can do, learn english and speak good english back to the electronics store clerk and all those who mocked at you and discouraged you.

                                there's a proverb that says revenge is always sweeter when u play the long game. since learning a language is a long game, talking and swearing back to them in english which they dont understand is a good way to take revenge back at them. so now revenge is a dish best served cold! give those pabu sai-ki (yes, i know how to swear in korean as well! learnt it from all those korean dramas and the hallyu wave courtesy of the korean entertainment industry and korean gov) back a piece of your mind what u think about them in english! hahaha!
                                Originally posted by bshi02 View Post
                                I'm sorry for making a mistake in measuring choke coil.I don't have enough practical eletronic knowledge..So I thought that Any choke coil on the mainboard has both solder joint of possitive and negative.. I did voltage test on solder joint of chock coil and chassis of ps/2 port and it display 1.96-2.00v.
                                In the same way,I also did voltage test on small chock coil which located next to 20 pin power connector and It display 5.02v.
                                And I always test CPU in other normal working mainboard before I test problematic mainboard in order to confirm whether CPU really works or not.
                                did u check the power supply as well? in a computer this old, the power supply may have failed also. a bad power supply could also be why the system wont start the post process properly. are there any bloated, swollen or leaking caps inside the power supply? can the power supply power up and start the post process of other systems as well?
                                Originally posted by cpt.charlie View Post
                                Maybe a stupid question, but have you checked the jumper configuration in the mainboard (CPU multiplier, FSB, Vcore....)
                                err... where are the configuration jumpers? i have looked at the photos for ages and i dont see them. can u kindly point out where they are on the board? this looks like an oem board. i doubt the manufacturer wanted config jumpers for the user to mess around with...

                                Comment


                                  #17
                                  Re: How can I desolder chock coil in PGA370 socket mainboard

                                  Originally posted by ChaosLegionnaire View Post
                                  err... where are the configuration jumpers? i have looked at the photos for ages and i dont see them. can u kindly point out where they are on the board? this looks like an oem board. i doubt the manufacturer wanted config jumpers for the user to mess around with...
                                  Ooops, i didn't check the pictures looking for jumpers so common back in the day.

                                  Comment


                                    #18
                                    Re: How can I desolder chock coil in PGA370 socket mainboard

                                    I'm sorry for too late reply..
                                    I persuaded my mother to become Electronics Repair Technician and said to her that It is impossible to work in Electronics Repair field without any good soldering tools. and it seems that She allowed me to become Electronics Repair Technician.
                                    So I ordered BC1,BCM2,BC3,JL02 soldering tip and T12 station of below link.
                                    https://www.aliexpress.com/item/32803295956.html
                                    and I finally received this T12 station yesterday!
                                    I tested it and found that it always retained targeted temperature, So from now on, I don't need to worry about burning up solder pad anymore!
                                    I replaced all of 6.3v 1500uf capacitor with 10v or 16v Samyoung NXB or samwha WL capacitor. But It don't solve problem of black screen..
                                    And Of course,I have tested this mainboard with antec vp 550 PSU of recently purchased, But it always display black screen.

                                    Now I'm at a loss what to do next in order to revive this mainboard..

                                    This mainboard(PYRAMID-5) doesn't have any configuration jumper(CPU multiplier, FSB, Vcore and so on).This mainboard is mutant of intel 810 chipset mainboard. Twenty years ago,I used to play Final Fantasy 8 PC version with this mainboard and celeron 366Mhz CPU,I remember that its onboard graphic especially 3D graphic perfomance is awful.
                                    anyway,It doesn't have any configuration jumper like other intel 810 chipset main board

                                    Comment


                                      #19
                                      Re: How can I desolder chock coil in PGA370 socket mainboard

                                      Originally posted by ChaosLegionnaire View Post


                                      repairing computers is not a skill u learn or pick up in school. u have to learn it by experience in the real world by finding broken computers and then fixing them. its what dicky96, momaka and many others here do. school can only teach u very basic things used in computers like electrical circuits, logic circuits, power supply circuits etc. the rest is you learning by experience.

                                      while its a nice job with decent pay, this job wont make u so rich that u can buy an apartment in the gangnam district of seoul unless u wanna go into data recovery. some companies that dabble in data recovery with clean room labs can bill customers thousands of dollars or millions of korean won. so if u wanna be a millionaire in korean won and make your first million easily, u can try going into data recovery but u also have to spend money first to pay for a clean room lab which can be costly also.

                                      otherwise, learning data recovery using software like gnu ddrescue for linux, mhdd, testdisk etc. is the way to go. typically u can bill clients a few hundred dollars or a few hundred thousand korean won for their data back depending on how many gigabytes and terabytes it was that u managed to recover.


                                      well, thats another language for you to learn: english. its very easy to pick up, dont worry. although, i've never been to korea or japan before but from what i heard from people who have been there, they said that people tend to run away from them if they speak english to the koreans and japanese. (no racism intended) so thats something u can do, learn english and speak good english back to the electronics store clerk and all those who mocked at you and discouraged you.

                                      there's a proverb that says revenge is always sweeter when u play the long game. since learning a language is a long game, talking and swearing back to them in english which they dont understand is a good way to take revenge back at them. so now revenge is a dish best served cold! give those pabu sai-ki (yes, i know how to swear in korean as well! learnt it from all those korean dramas and the hallyu wave courtesy of the korean entertainment industry and korean gov) back a piece of your mind what u think about them in english! hahaha!
                                      When I was a high school student, It was my wish to complete understand any book which written in english. So I relatively put an effort into English than other subjects. But I failed to go to university owing to my SAT scores is very low...(yes,,I really hate to study for any kind of exam,And it is tremendous tragedy for me to be born in south korea where have been decided one's social position with SAT scores)So I was decided to go vocational technology school. But its quality of education is terribly crap! Aim of their education is not to learn soldering skill or understanding electronic part, but to pass electrician certification exam which give advantage in getting a job. I was really outraged,and quit this fucking holy crap school and totally got it bad for video game...

                                      I cannot speak any English word.I also run away like other stupid korean ,whenever I met any foreigner in the street who tried to ask any question in english to me. It was possible for me to understand english writting to some degree..But It is totally impossible for me hearing and speaking in English, despite of my endeavouring for english..

                                      A few month ago, My father was dead and Now my mother want me to get any job which give sufficient pay to live in, I don't have brilliant brain enough to get job offers from data recovery company,But I really loved origami when I was elementary student and I think I have decent manual dexterity which gave me A grade in art classes when I was middle and high school student.So I think I can master soldering skill someday as I have done in art classes and origami.
                                      Last edited by bshi02; 03-12-2021, 08:32 AM.

                                      Comment


                                        #20
                                        Re: How can I desolder chock coil in PGA370 socket mainboard

                                        Nice to see you are happy with your T12 soldering station

                                        So regards your motherboard, you need to start at the basics

                                        Test your CPU is good on your other motherboard. Once you know it is good, fit it to the bad motherboard, and with heatsink and fan fitted.

                                        Fit a CMOS battery

                                        Don't fit any RAM

                                        I see this motherboard has an onboard speaker - However I would connect a PC speaker or beeper to the front panel connector on the motherboard, if there is a connection for one. If you can do that, just to be sure, test the speaker is working using your good motherboard so we don't get following imaginary faults.

                                        This is an odd looking motherboard, it looks very much like an MSI MS-6178 that I am trying to fix myself a the moment, but says it is Samsung.
                                        https://www.badcaps.net/forum/showthread.php?t=93613

                                        Do you have a user manual for this motherboard, I couldn't find one.

                                        Also post in the Desktop motherboards / Schematic requests section on this forum and ask if anyone has a schematic for Samsung BA41-00143A or SAMSUNG M5317 MAGIC STATION

                                        At the least can you tell me what chipset this motherboard is? (post here the part numbers of the two green/black intel BGA chips - one near the CPU socket and the other near the Dimm sockets)


                                        Can you confirm the fault - does it power on when you press the ATX power button (the standby/on button), does it power back down if you hold the button in for 5 seconds?

                                        That will do to start with, do ALL those things then reply here
                                        Thanks
                                        Last edited by dicky96; 03-12-2021, 11:51 AM.
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