Upgrading the Raspberry Pi 4 to 16 GB?

MadEDoctor, the YouTube creator known for their Raspberry Pi 4 RAM upgrade projects, is at it again. In their latest endeavor, they aim to take the popular single board computer to new heights by upgrading it to 16GB - albeit with some caveats.

Previously, MadEDoctor had successfully upgraded the RAM of the 1GB Raspberry Pi 4 to 8GB. However, this was not enough for them, and with the help of a hot air rework station (similar to the ones featured on our "Best Soldering Irons" page) and a generous donation, they undertook the challenging task of upgrading the RAM to 16GB.

The blue soldering mat, fume extraction, and an ample amount of Kapton tape were brought out. Their purpose was to protect the other chips on the board during the RAM swap. The goal was to replace a 4GB Micron LPDDR4 chip (D9ZQX) with a 16GB Micron LPDDR4 (D8CBG). The original RAM was heavily coated in flux and then heated to 420 degrees Celsius using hot air to remove it. The RAM chip is held in place by a BGA (Ball Grid Array), so all solder balls need to be loosened by the heat before the chip can be extracted. As in previous operations, MadEDoctor cleaned up the pads using a little lead solder and solder wick to ensure they were prepared for the replacement chip.

Since the donated 16GB RAM chip lacked "solder balls," a stencil and leaded solder paste were utilized to "re-ball" the chip. Once all of the solder balls were positioned, the chip was prepared for soldering onto the Raspberry Pi 4.

Does 16GB RAM work with the raspberry Pi 4?

MadEDoctor has found mixed results when attempting to boot a 64-bit Raspberry Pi OS micro SD card on the Raspberry Pi 4. While the boot screen initially displays 16GB of RAM, the Pi fails to boot and instead halts on a black screen. However, when trying to boot RISC OS, the Pi successfully boots but only recognizes 4GB of RAM. Despite this setback, MadEDoctor has released a video detailing their efforts and plans to follow up after further investigation. We extend our best wishes to MadEDoctor in their hack.