The Raspberry Pi 5's 3GHz Limit Is Lifted, Thanks to a "Very Not At All Recommended" Firmware

A firmware limit placed based on Broadcom's recommendations can now be lifted, allowing clock speeds above 3GHz for the first time.

Gareth Halfacree
1 month agoHW101

The artificial 3GHz clockspeed limit enforced on the Raspberry Pi 5 has been removed — if you're willing to install a "very not at all recommended firmware," and if your particular board was a winner in the silicon lottery.

The Raspberry Pi 5 launched late last year as the most powerful single-board computer in the Raspberry Pi range, by some considerable margin. That extra power over the Raspberry Pi 4 and earlier models, though, wasn't enough for some — and, like all models, it's possible to tweak the clocks on the Raspberry Pi 5 to gain extra performance.

The Raspberry Pi 5's 3GHz clockspeed limit has been lifted, with 3.14GHz the new record to beat. (📹: Jeff Geerling)

Those doing so, however, ran into a roadblock: while many, though not all, Raspberry Pi 5 boards could happily overclock from their stock 2.4GHz to an impressive 3GHz, that was it. The reason: a hard limit placed by Raspberry Pi within the firmware, preventing the processor from running above this speed owing to claims by Broadcom that going beyond this would be outside the capabilities of the phase-locked loop (PLL) in the BCM2712 system-on-chip (SoC).

Until now, anyway. A new firmware, released on GitHub yesterday, removes the 3GHz limit and allows for clocking above this speed. YouTuber Jeff Geerling was one of the first to take it for a spin, successfully overclocking a Raspberry Pi 5 to an appropriate 3.14GHz — with variable stability, it must be admitted.

Raspberry Pi's Alasdair Allan took to Mastodon to celebrate Geerling's achievement — but describes the firmware as "very not at all recommended." Thus far, no permanent damage has been reported, but it remains possible: stability beyond 3GHz is questionable, and the additional voltage bump required to counteract that has the potential to permanently damage boards.

For those who would like to try it anyway, the firmware can be downloaded from a comment on the Raspberry Pi firmware GitHub repository.

Gareth Halfacree
Freelance journalist, technical author, hacker, tinkerer, erstwhile sysadmin. For hire: freelance@halfacree.co.uk.
Latest articles
Sponsored articles
Related articles
Latest articles
Read more
Related articles