Tasty Treats–reflowing a laptop motherboard
Reflowing, what on earth are you babbling about?? Spilling coffee on a laptop?
No that would be an article about how coffee is not to blame for my stupidity, I am taking about repairing a defective computer component.
Various computer components have a flaw related to ‘cold’/poor solder joints that may crack/degrade after many heat/cool cycles, these joints provide electrical connections between electronic components and if these connections degrade there will likely be a failure or partial failure or the component containing the troublesome joint .
Contemporary computer systems generate a lot of heat while in operation and so cause cycles in operational temperature (in 10 years time when the low energy/heat ARM architecture has taken over as the dominant CPU architecture and GPUs are built on 8nm processes this may not be the case).
After a few years of use these degraded joints may show themselves as they did with my beloved Dell Latitude D820, a fantastic magnesium alloy dockable laptop with a beautiful keyboard and 2 hard disks, in this case my graphics card stopped outputting to the inbuilt LCD and produced scrambled graphics when connected to an external VGA display (no, I’m not a Dell salesman I am just trying to justify why I spent the time fixing this thing… apart from curiosity).
The technique detailed in this post can also be used to repair a XBOX 360 that has a bad case of red eye/Red ring of death
DISCLAIMER: this is a recount of my experience if you read this then get inspired to perform a similar operation and mess up then you may need to grow up and admit its your fault as I take no responsibility for your actions and decisions
Ok what is reflowing?
In short reflowing is bringing the temperature of the degraded solder connecting components to a point where it become liquid/flows and then disengaging the source of heat so that the solder can cool slowly and hopefully re-establish the joints.
So will I get a soldering Iron?
No, most components are BGA/surface mounted and although technically may be soldered using an iron you would waste too much time and need to be a master of soldering…. so I am going to suggest a much better approach, using an ambient heat source.
Ambient? what do you mean? mood heating?
I am suggesting putting your components in the oven or using a heatgun/hairdryer to melt the solder.
I tried the hairdryer method and although it worked well with a faulty XBOX 360 is was not so successful with my D820 which has a NVidia chip that has known heat problems which i supposed meant that a higher temperature than what a hairdryer can provide would be required to reliably reflow the D820.
Easy as Preheat, Prepare and Cook
The steps are as follows
- Preheat the Oven to 220C
- Remove all extraneous components e.g fans, plastics, keyboards, displays and disassemble the problem device
- Wrap all non-relevant portions of the component in aluminium foil
- Cook the component for 12 minutes or so
- Turn off the oven
- Turn on air extraction systems and open all windows/vents
- Open the oven door
- Leave the component to cool to room temperature before removing from the oven
- Reassemble the device (in my case the D820)
- Turn on and hope for the best
Preheating the Oven
A Powered-on faulty laptop
Disassembling the Laptop
Preparing the laptop by exposing only the troublesome components
Powering a now fully working laptop
A month later my D820 is still working, even after burning it in for 2 weeks using a 3d stress test and no this is not my only computer its one of a bajillion but this is the one I wrote my undergrad and postgrad dissertations on and so I’m nostalgic about it and want it to live forever