Remove Lenovo black Glue under the chipset?

[tomodachi]

In 2025 this is still problem... im about to reball cpu on legion 5.. i think. best way is separating the chip and the board at the corners with thin tool while balls are melted!

Apply usual reflow temperature, when balls melt use a thin blade to seperate chip from board by sticking it under and turning it, that is the way.
Some BGA chips require extreme force to come off but in the end they don't get damaged so don't worry
in some cases pcb paint might come off but it is repairable.
Be patient , it totally worth the effort

[mon2]

What about using a conformal coating remover like the one from MG Chemicals? I think we have a bottle incoming to repair a CPC4 truck ECU where the BGA bonds break over time so a local auto shop has requested this service. For the CPC4, the hard clear coating is definitely 'conformal coating' as used by automotive firms. Not sure if the same chemical can work for your case.

8310A-55ML
CONFORMAL COATING
STRIPPER-GEL, WITH BRUSH CAP

https://mgchemicals.com/products/con...emover-gel/