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If I disassemble an iPad, is it possible to replace the internal flash mass memory with a 128GB Samsung SSD 1.8"? what is kind of the iPad’s flash mass memory? does the quality of the internal multimedia decrease? Would iTunes support the modified iPad? Would I be able to install the iOS 4.2? Thanx for the answer.
No. The NAND flash is soldered to the main board, and it does not have an interface that’s compatible with an SSD (or space inside for a drive). It is hypothetically possible to replace the flash chips with larger capacity chips, but that would require a sophisticated surface mount de/soldering setup. In English: a semiconductor company could do it, but probably not an individual.