Raspberry Pi blocks RAM chip swaps on newer boards via firmware

Raspberry Pi has confirmed that on newer boards the firmware ties a machine to the amount of RAM it left the factory with. A user who replaced the original 2 GB memory package on a Compute Module 5 with a known-good 4 GB chip taken from another CM5 found that the system still reported only 2 GB. The exchange on the company's official forum is titled "Raspberry Pi blocks changing RAM chips".

What the firmware actually does

The memory in question is LPDDR soldered directly to the board, so any swap needs BGA rework equipment rather than a socket. According to Raspberry Pi engineer and forum moderator PhilE, the configuration programmed into these boards goes beyond a simple capacity record: memory density, organisation, tuning and timing parameters are stored for each SDRAM supplier and configuration the company supports. An identical part with the same part code can still work as a repair, but an alternative chip of the same capacity is no longer guaranteed to boot, and moving officially supported memory between boards of different capacities is not a route to an upgrade.

Raspberry Pi's reasoning

The company says the aim is to stop third parties from buying low-capacity boards, substituting cheap memory of uncertain origin and reselling the result as a higher-capacity model. Such units never passed Raspberry Pi's own validation, and when they misbehave the complaints and warranty requests are aimed at Raspberry Pi rather than at the reseller. Because the company buys memory in large volumes on negotiated commercial terms, it argues there is little legitimate financial incentive for these swaps anyway.

Reaction and how to check a board

The change is not new: the blogger Jeff Geerling notes that the firmware update that disabled the swaps dates from late 2024, and that the only practical workaround is running firmware from 2024-09-10 or older. A GitHub issue in the rpi-eeprom repository describes a Pi 5 8 GB board with a Micron D8CJN LPDDR4 chip that fails to boot after EEPROM releases dated 2024-09-23 or later, with the green ACT LED blinking eight times to signal SDRAM failure. Reaction has been split: supporters point to counterfeit boards and the support burden they create, while critics argue buyers should be able to repair or modify hardware they own. The practical advice is to verify a board's factory configuration — the revision code returned by vcgencmd otp_dump | grep 32 or cat /proc/cpuinfo | grep Revision can be matched against Raspberry Pi's published revision table, and a board booted without an SD card prints its factory RAM size on screen.