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Lardzor

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    Lardzor got a reaction from TechyBen in In regard to Louis Rossman's video on baking graphics chips.   
    Recently Linus Tech Tips released a video about Fixing graphics cards by baking them in an oven to reflow the solder on solder joints that have cracked due to thermal expansion. Louis Rossman has a channel where he argues that this is a bad idea and seems to imply that baking a circuit board in an oven is stupid. 
     
    https://www.youtube.com/watch?v=E9aZZxNptp0#t=2m25s
     
    Most modern graphics card circuit boards and flip-chip CPU/GPUs have already been baked in a reflow oven during the manufacturing process.  Only some of the components that are NOT surface mount components like power plugs and basically anything that pokes all the way through the circuit board and pokes out the other side are wave soldered on in a second stage. Those components may not be designed for high temperatures, where the surface mount components are. So baking a circuit board in an oven is not a new experience for a graphics card.
     
    I did a little research on flip chip bonding and I found a very informative video about flip chip bonding with the little bumps that bond the chip to the substrate that Louis Rossmann refers to in his video at 2:25
     
    https://www.youtube.com/watch?v=vKj3eXgyC5c#t=19m40s
     
    Yes, their are bumps that bond the chip to the substrate, and yes, the bumps are completely encased in underfill and you can not get to them, but what Louis seems unaware of is that the bumps are actually mad of solder (solder bumps) and that means they can be reflowed.
    It briefly mentions at 29:30 how there can be solder joint fatigue in the solder bumps due to differences in thermal expansion coefficients between the chip and the substrate and the importance of using underfill.
     
    My link skips ahead to flip chip bonding. The first part of the video deals with wire bonding with non-flip chips and not relevant to this topic.
     
    TL:DR  Don't sweat it Linus, you got the science on your side.
     
    Regards,
    Lardzor
  2. Informative
    Lardzor got a reaction from vanished in In regard to Louis Rossman's video on baking graphics chips.   
    Recently Linus Tech Tips released a video about Fixing graphics cards by baking them in an oven to reflow the solder on solder joints that have cracked due to thermal expansion. Louis Rossman has a channel where he argues that this is a bad idea and seems to imply that baking a circuit board in an oven is stupid. 
     
    https://www.youtube.com/watch?v=E9aZZxNptp0#t=2m25s
     
    Most modern graphics card circuit boards and flip-chip CPU/GPUs have already been baked in a reflow oven during the manufacturing process.  Only some of the components that are NOT surface mount components like power plugs and basically anything that pokes all the way through the circuit board and pokes out the other side are wave soldered on in a second stage. Those components may not be designed for high temperatures, where the surface mount components are. So baking a circuit board in an oven is not a new experience for a graphics card.
     
    I did a little research on flip chip bonding and I found a very informative video about flip chip bonding with the little bumps that bond the chip to the substrate that Louis Rossmann refers to in his video at 2:25
     
    https://www.youtube.com/watch?v=vKj3eXgyC5c#t=19m40s
     
    Yes, their are bumps that bond the chip to the substrate, and yes, the bumps are completely encased in underfill and you can not get to them, but what Louis seems unaware of is that the bumps are actually mad of solder (solder bumps) and that means they can be reflowed.
    It briefly mentions at 29:30 how there can be solder joint fatigue in the solder bumps due to differences in thermal expansion coefficients between the chip and the substrate and the importance of using underfill.
     
    My link skips ahead to flip chip bonding. The first part of the video deals with wire bonding with non-flip chips and not relevant to this topic.
     
    TL:DR  Don't sweat it Linus, you got the science on your side.
     
    Regards,
    Lardzor
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