Substituting / Replacing Capacitors

Discussion in 'General Electronics Chat' started by Barry M, Mar 9, 2009.

  1. Barry M

    Thread Starter Active Member

    Feb 11, 2009
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    I have 3 blown caps on a motherboard and want to replace them. The ones on it are 1500uF 16V, would it be ok to replace them with 2200uF 16V or 2200uF 25V? 1500 seem to be scarce where I am.
     
  2. mik3

    Senior Member

    Feb 4, 2008
    4,846
    63
    Sometimes is fine but sometimes not.

    Why the capacitors blow? Have you thought of that?
     
  3. beenthere

    Retired Moderator

    Apr 20, 2004
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    Space on MB's is usually tight. You might have vertical room, but probably not horizontal. So you can place taller, but not fatter, capacitors. Measure the diameter of the old ones and search on that dimension.
     
  4. thatoneguy

    AAC Fanatic!

    Feb 19, 2009
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    I'd suggest getting a complete kit.

    http://badcaps.net

    They have lots of information about the problem you are experiencing, and full kits for a variety of motherboards.

    If the problem you are having isn't described at that site, or your motherboard is less than 2 years old, something else was probably involved with the capacitors demise, and there is more damage than just that. In that situation, test power supply under load, if good, replace motherboard. If power supply is also bad, it's usually cheaper to get a new system, and copy your data from your old one.
     
  5. Barry M

    Thread Starter Active Member

    Feb 11, 2009
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    0
    Thanks for the help, think I will chance it with the bigger size, its an old P4 board.

    Mik3: Could be part of the plague (reading on that made me check them), it could be the PSU because its the second mobo to die in that case, both took over 2 years though, or I could just be lucky like that and its coincidence. Then again could be the ambiet temp. in here is 25c and its a box I had running 24/7.

    beenthere: Its caps between the CPU and the I/O ports, fortunately on this mobo you can fit a bus in there.

    thatoneguy: thanks for the link but unfortunately the prices and time make it cheaper and quicker for me to pay premium here to get them delivered.



    I may not get anywhere with it, I cant get the caps off ... which is pretty hilarious when I think of the amount of times I accidentally removed an entire solder job by accident or watched pins on an existing job dissapear as the component slips through the PCB. Ive tried leaving it for a while and also adding flux and solder to get it going. I dont really want to go above 40W on it.
     
  6. thatoneguy

    AAC Fanatic!

    Feb 19, 2009
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    If it is a P4, your power supply may be supplying too much ripple for good caps on the motherboard to handle. This would explain same thing happening to motherboard twice.

    If a new system is out of the question, replace the power supply, or at least the caps inside.

    For tips on desoldering/soldering motherboards, see the badcaps link above. Motherboards have several layers and component holes are plated through to contact all layers, so it can be a bit difficult to do without delaminating/destroying the board.
     
  7. beenthere

    Retired Moderator

    Apr 20, 2004
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    Yes, I would hate to suggest the old method of heating the leads and banging the MB on a table top to let inertia remove the caps.
     
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