The Apple M1 processor features integrated memory directly on the chip to reduce latency, power, and size. While this design may be good for the overall user experience it does not bode well for upgradability requiring users to pay up for a more expensive model. Some Chinese engineers have recently shown how it is possible to upgrade the soldered memory and storage components given you have the time, skills, and money. The DRAM and NAND chips are soldered to the M1 chip and motherboard but can be removed and replaced with higher capacity chips using a specialty soldering station. The engineers upgraded the base model M1 Mac Mini with 8 GB RAM and 256 GB storage to 16 GB RAM and 1 TB storage. The upgrade didn't require firmware modifications according to the source which is very impressive if true.
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