The 3DS uses Lead Free Solder. This solder is prone to brittle joints cracking over time. I am pretty sure this is a problem with some of the solder joints cracking and not the BGA chip itself. This is similar to the issues with the PS3. Lead free solder combined with a BGA chip is a recipe for eventual failure. This is why people had to put their PS3s in the oven to reball them. This solder should be replaced with 60/40. That is all.
