The Capacitor Failure Issue - The Equipment and Parts you Need to Fix the Problem  
  I have learnt a good method of replacing capacitors on motherboards from Topcat of the Badcaps site. If you are not confident to replace the caps yourself and you live in the US then you can pay him to repair your motherboard professionally. His site also has great forums where you can get a lot of knowledge and assistance about this issue. We will start with what you need to get the job done properly.  

Get a good solder station : It is not necessary to get a digital one for this job, they are more expensive but feel free if you have the money. An analog is sufficient and it will be turned on full at 450oC all the time. You should choose one from a major manufacturer like Hakko, Goot, Weller or ERSA which I use. I chose ERSA because it is available locally and all the parts/tips/sponges are also available locally which will prolong the life of the station, rather than ordering a japanese station from far and not having good access to the parts. You should also order 2 extra sponges and the correct tips from the supplier. Get 3 tips including one standard. It may be difficult or expensive to find them later. You will find out your own personal preference of tip by using all 3. If I was to choose a different station I would buy one from Hakko or Goot, they are great Japanese equipment. A good solder station also has a stand which includes a sponge. This is very important because you will need somewhere to safely put the iron while you are messing about with the board. The wet sponge is also important because you must constantly clean the iron of excess solder using the sponge in order to do a nice job and to avoid splatter.

  Here is a pic of my soldering kit. Click on the photo for a larger version. Please note that I do not use the solder wick or the solder paste for working on motherboards.  
  Don't get less than a 60W station : The higher wattage is recommended because the traces in the board eat up a lot of the heat from your iron. The wattage does not mean more temperature but it means that temperature can be maintained with bigger jobs. You will not be getting anywhere with a 22W soldering iron it just will not melt the solder to remove the old caps. The 60W will be also useful for doing other jobs like making stereo cables or doing some electrical wiring.  
  Get an antistatic solder station : As you are working with sensitive electronic components you should try to get an antistatic solder station. The ERSA Analog 60 which I use is actually not antistatic but it is modified with the antistatic ERSA Ergo Tool and I always wear an antistatic wrist strap on the wrist that is holding the iron and connect the other end of the wrist strap to a metal part of the computer case while it is plugged in. At least make sure that the soldering station is grounded. If you choose ERSA I would recommend instead the Analog 60a which is MIL-SPEC antistatic but it is much more expensive.  
  Do I need an expensive hot air pencil and desoldering tool? : You might think that you need expensive kit. We are talking about $1000 and above. These would make your job very easy but are an unnecessary expense if you are to recap only a few boards. Start small and you have not wasted too much money if you dont have success. Then when you move on to bigger projects you may wish to invest in better equipment. With a $100 soldering station, accessories and some good practice you will successfully replace the capacitors of motherboards.  
  What kind of soldering iron tips will I need? : This was actually something suprising to me when I started to replace caps. I immediately though that I would need the thinnest tip to do a good job. This is actually incorrect because the thinner and the longer the tip, the less heat is transferred from the heater of the iron to the component you are working on.  

You can see in the above photograph the Standard chisel tip which came with the iron and also two loose tips, the thinnest one was my choice and the conical one was recommended by the shop owner. Common guidelines say that you need a tip which is the same width as the pad which you are soldering. Actually the only tip which keeps enough heat to melt the original solder on the motherboard is the Standard chisel tip. It is much wider than the pads on a board but I am using it so the thin corner contacts the pad and the rest of the tip contacts the capacitor lead. It works very well for me.



  What other equipment will I need? : at the minimum you will need some 60/40 solder. I am using Alpha-Fry Technologies 60/40 solder which is 2.2% flux and 0.8mm diameter. It is probably not the optimum but the best that was available. The 0.8mm i have found is good for the job, maybe a little too big but fine. You will also need a solder sucker or pump. Get a standard sized one like you see in the first photograph (the yellow/black tool) so you will have enough suction. You will also need some lead clippers to clip the leads of the new capacitors you installed. Normal big wire clippers will not do a good job, you need proper mini wire clippers. I am using the green ones in the photograph which are from Pro's Kit of Taiwan (8PK-30D) they are great. You will also need an antistatic wrist strap and one canned air spray and also flux-off spray. The most important is a board holder which we will discuss below. All that is the minimum you will need to do a proper job. It shouldnt cost too much at all and it is a good kit to have for doing all sorts of repairs. Don't forget safety also, wear your normal prescription glasses or get some cheap eye protection glasses from your hardware store. The solder can make hot flux splatters and you will be working with your face near the board.  
  What shall I use for a board holder? : you could go and waste your money on a special board holder or you could find two standard sized wood clamps from your garage. If anybody is doing any kind of woodwork in there you should find some. It is very important to have a board holder for when you remove the caps.  
  Above you can see the two wood clamps attached upside down to the table. I have covered the metal bits of the clamps with electrical tape to protect the motherboard from scratches. You will see on the next page the board held by the clamps.  
  What kind of capacitors should I buy : you will have to find a source of good quality Low ESR capacitors. The regular ones from your local store will not be any good. I would recommend that you try RS Components for the Panasonic FC capacitors. They are great for motherboards. You will only be able to get 10mm and above width there though and you may have difficulty replacing the 8mm caps if they are in a closely spaced array. It will be possible with bending the leads of some caps so they lean to the side, it will look ugly but the board will still work properly. Other brands you could get are Rubycon MCZ, MBZ, ZA, ZLG, ZL, ZLH, YXG, YXH, YXF in that order. Dont worry if you can only find ZL or YXG they are great, easier to find and cheaper than the higher specced Rubycon caps. You could also try Sanyo or Nichicon caps but I am not familiar with the series to advise you the specific ones to get. Make sure that they are Low ESR anyway. Do not use old capacitors from another motherboard, you dont know the condition of them and then you just add another variable to finding out why the board does not post after you are finished. The old capacitors also do not have long enough leads to help you install them properly.  
  What values of capacitors should I replace? : You should replace all values 1000uf and above which are either failed or are from suspect manufacturers even if they have not failed. You may also like to replace large 8mm caps of small value like 330uf 25V which are seen on some motherboards. If the cap is not in the region of 8mm width and does not have vents carved into the top and it is small value then it will probably not fail. In the case that you see a small cap has vented or is getting very hot then you should replace it. Please ask on the badcaps forums if you are not sure which caps to replace. A photograph of your board should be posted there also to assist those giving advice.  
  What values should I use to replace the capacitors with? : This is the subject of some debate and also personal preference. You can actually put different values but you should try to follow some rules. You could replace 6.3V caps with 10V caps without problem. It is not recommended to reduce voltage however. If you increase voltage too much you will be buying a cap which will be much wider than the original one and it may not fit. You should also try to stay within 30% of the uf value of the original cap, so if you have a strange cap value which is difficult to find you could replace it with a higher uf which is within 30% of the lower value. Again, please ask on the badcaps forums for assistance if you are changing the cap values. You can probably get away with putting quite different values but you will need to check that someone has successfully done that before proceeding. Like for instance I was suprised to see that 330uf 25v caps can be replaced by 1000uf 16V without problems.  
  Read on to the next section to learn the technique of motherboard capacitor replacement that I learnt from Topcat of badcaps.net.  
A serious problem that every technician should learn about
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