xodaraP
Legendary
Hi guys,
I bought a KI board off ebay as parts/not working, originally intending to use it as a parts board to fix another KI board for a friend that has issues. It turned out not to be needed as a parts board, so I thought I'd attempt to repair it. Long story short, someone has attempted a reflow on the CPU and made a fairly big mess of it. They have used lead free solder which has not worked well with the original leaded solder, causing a giant bridge across pretty much all the pins on the CPU. I removed the heatsink and ended up with this:
Loads of flux everywhere (from both the original reflow attempt from the seller, and somewhat me trying to fix the damage), completely bridged pins all the way across and..... yeah.
Given that if this board has even attempted to be booted with this mess, the CPU is most likely toast, I'm going to remove this CPU and replace it. I don't think it could have been salvaged as it was but even if it could, I was more focused on salvaging the board itself with as little damage as possible, not the CPU. With this in mind, I used a hot air gun at 300C and then at 400C (to get the crap non leaded solder to flow) and used a sharp knife to lift the pins off the board and bend them out of the way. By using the lower temperature first I was able to limit the risk of damage by pulling the pins out of the way that still had the original solder on them, then the last of the pins came off with the 400C hot air.
I ended up being left with this
Still so much solder left across so many of the pins. And that flux, yuck.
After reflowing all the pins with a soldering iron (which is much easier when there's not a processor with tiny pins there) - I ended up with this
As you can see, I did lose 1 pad while removing all the pins from the board. But considering there was about 200 I can live with 1 (would've been nicer if it was a non connected pin, but that's life) - I then proceeded to clean it up with isopropyl alcohol and this is the final result post removal:
I'm actually pretty damn happy with how it turned out in the end - unfortunately what this does mean is I need a replacement for a fairly rare CPU. The original is not salvageable and as I said before I feel like even if it was it is probably fried. But in the meantime I have a nice clean board ready for it to be installed onto when I do find one. If you have a scrap board that uses this type of CPU, please let me know what you would like for it so I can get this KI back up and running
I bought a KI board off ebay as parts/not working, originally intending to use it as a parts board to fix another KI board for a friend that has issues. It turned out not to be needed as a parts board, so I thought I'd attempt to repair it. Long story short, someone has attempted a reflow on the CPU and made a fairly big mess of it. They have used lead free solder which has not worked well with the original leaded solder, causing a giant bridge across pretty much all the pins on the CPU. I removed the heatsink and ended up with this:
Loads of flux everywhere (from both the original reflow attempt from the seller, and somewhat me trying to fix the damage), completely bridged pins all the way across and..... yeah.
Given that if this board has even attempted to be booted with this mess, the CPU is most likely toast, I'm going to remove this CPU and replace it. I don't think it could have been salvaged as it was but even if it could, I was more focused on salvaging the board itself with as little damage as possible, not the CPU. With this in mind, I used a hot air gun at 300C and then at 400C (to get the crap non leaded solder to flow) and used a sharp knife to lift the pins off the board and bend them out of the way. By using the lower temperature first I was able to limit the risk of damage by pulling the pins out of the way that still had the original solder on them, then the last of the pins came off with the 400C hot air.
I ended up being left with this
Still so much solder left across so many of the pins. And that flux, yuck.
After reflowing all the pins with a soldering iron (which is much easier when there's not a processor with tiny pins there) - I ended up with this
As you can see, I did lose 1 pad while removing all the pins from the board. But considering there was about 200 I can live with 1 (would've been nicer if it was a non connected pin, but that's life) - I then proceeded to clean it up with isopropyl alcohol and this is the final result post removal:
I'm actually pretty damn happy with how it turned out in the end - unfortunately what this does mean is I need a replacement for a fairly rare CPU. The original is not salvageable and as I said before I feel like even if it was it is probably fried. But in the meantime I have a nice clean board ready for it to be installed onto when I do find one. If you have a scrap board that uses this type of CPU, please let me know what you would like for it so I can get this KI back up and running