An vital consideration about Pi 5 overclocking
Silicon lottery.
Now that the Raspberry Pi 5s been available (at the least in most areas) for just a few months, extra individuals began messing with clocks, attempting to get probably the most velocity attainable out of their Pi 5s.
In contrast to the Pi 4, the Pi 5 is usually snug at 2.6 and even 2.8 GHz, and a few Pi 5s can hit 3.0 GHz (however no larger—extra on why tomorrow).
After some testing, I discovered the default 2.4 GHz clock on the Pi 5 is pretty much the efficiency sweet spot, and after a lot extra testing lately, I can verify that is nonetheless the case, testing quite a few Pi 5 samples.
Additionally in contrast to the Pi 4, the Pi 5’s not very choosy about cooling. Whereas the chip runs just a little hotter, it does not want unique cooling like spraying ice, water cooling, or LN2, to run at its highest attainable clock speeds. It does want some cooling, however I’ve discovered the most important issue affecting how briskly your Pi 5 will go is the chip itself.
The silicon lottery mainly states that amongst samples of the very same silicon chip—on this case the BCM2712 on the coronary heart of the Pi 5—there are variations affecting efficiency, thermals, and many others.
These variations are virtually imperceptible on the 2.4 GHz default clock Raspberry Pi selected for the board, however they will have an effect on how briskly your Pi 5 can go, it doesn’t matter what cooling answer you utilize.
To show that, over the previous 5 months, I’ve slowly acquired 10 Pi 5s from distributors all over the world (1 at a time), to ensure they arrive from totally different batches, and I have been testing overclocking efficiency on every. I additionally had one other mission slated for quite a few these Pis (which I am going to reveal tomorrow), however one factor I needed to quantify is how most of the Pi 5s would hit 3.0 GHz.
And the reply? Out of the ten I purchased, just one! It was an 8GB mannequin (I did purchase just a few 4GB Pi 5s as nicely, since the performance characteristics can be slightly different, and it runs at 3 GHz reliably with any type of lively cooling.
I’ve examined it with:
- Raspberry Pi’s personal Energetic Cooler
- Argon THRML (an enormous tower cooler for the Pi 5)
- Argon Neo (a case with a bigger heatsink and PWM fan for the Pi 5)
- EDATEC Pi 5 Fanless Case (a high + backside heatsink cowl for the Pi 5)
And in all circumstances, it labored fantastic.
I examined my different Pis with all these cooling options, and even tried a pair on my massively-overkill water cooling setup, and it doesn’t matter what, none of them reached 3.0 GHz. The closest I acquired was 2.9 GHz on a few them. The remainder maxed out at 2.8 GHz.
The results of that 3.0 GHz overclock? A touch-improved Geekbench 6 score of 1662, versus 1507 with no OC. To realize that 10% speedup, it ate up about 20% extra energy, so efficiency-wise, it is not price it.
Additionally, for those who’re solely involved about uncooked efficiency and effectivity, an RK3588-based SBC is likely to be the higher possibility regardless—it offers virtually double the utmost efficiency, utilizing about the identical energy! (however software program points and vendor / neighborhood help.)
Backside line: not each Pi 5 can obtain a 3.0 GHz overclock—actually, in my testing, most cannot. 2.4 GHz is probably the most environment friendly clock for the C0 BCM2712 silicon operating on the Pi 5, at the least primarily based on my testing.
Extra on the Pi 5’s silicon coming tomorrow—which occurs to be Pi Day 🙂