New 2GB Raspberry Pi 5 has 33% smaller die, 30% idle power savings

https://www.jeffgeerling.com/blog/2024/new-2gb-pi-5-has-33-smaller-die-30-idle-power-savings

by ingve • 2 years ago

214 84 2 years ago

GGO• 2 years ago

is there going to be D0 stepping for the 8GB version?

jsheard• 2 years ago

I don't see why there wouldn't be, it's cheaper to manufacture with seemingly no downsides. They probably won't revise the 4GB and 8GB versions until their stocks of the original stepping are used up though, and once they do introduce revised versions it may be a lottery which version you get for a while.

AstroJetson• 2 years ago

I'll bet they just slipstream them in. There was a huge backlog of the 8GB, that now looks pretty much cleared out. So it could be awhile before the D0 show up.

hajile2• 2 years ago

TSMC charged just a hair under $4000 per 16nm wafer in 2020.

Wafer calculators at 0.2 defect/cm2 on a 300mm wafer gives 950 fully-good dies out of 1061 for the old die (~89% good) and 1469 fully-good dies out of 1584 (~93%) for the new dies.

Dividing that out gives $4.21/chip for the old chip and $2.72/chip for the new chip. At $80 for an 8gb board, that represents a ~1.9% increase in profit per board. For the $60 4gb version, it's more like 2.5% increase in profit per board.

In real-world terms, if they sell 10M Pi5 units with the new chip, they'll have an extra $15M in the bank in saved production costs alone (minus whatever costs to strip everything out and tape out again). Furthermore, the new chip gets cheaper with every chip they make as the R&D costs get more and more diluted.

rjsw• 2 years ago

You had speculated in a previous thread that the new die could result in power savings, good to see some real measurements.

toastau• 2 years ago

Nice work!

0cf8612b2e1e2• 2 years ago

  Some of the power savings could be chalked up to less RAM, because more RAM requires more power. But that doesn't explain all the results.

Is there a calculation to estimate RAM power consumption? I keep wanting to get a low powered N100, and have been wondering if I use say 8 vs 16GB RAM, would that make a measurable power difference?

Mistletoe• 2 years ago

A small amount.

As a rule of thumb, you can expect to allocate around 3 watts of power for every 8GB of DDR3 or DDR4 memory.

0cf8612b2e1e2• 2 years ago

Similar for DDR5?

In the context of a N100, 3W is actually pretty high. Many of these systems idle around 10W.

mallets2• 2 years ago

That's a ridiculous amount of power, is that answer from a LLM? It's in the range of ~150mW for LPDDR4. Around half that in idle.

adgjlsfhk1• 2 years ago

https://www.servethehome.com/ddr4-dimms-system-power-consump... which is the only source I've seen that looks even vaguely trustworthy gives 2 watts per 8 gb of ddr4 (and ddr5 should be about 10% lower since it drops to 1.1 from 1.2 volts assuming similar amounts of current).

hajile2• 2 years ago

Their numbers seem to indicate that Pi disabled parts of the chip in firmware instead of physically lasering them out. This leaves those parts still leaking some current and explains the power difference.

moffkalast5• 2 years ago

8 vs 16GB RAM, would that make a measurable power difference?

I think the short answer is.. it depends. Current draw depends on usage, supposedly from 10% at idle up to full when doing massive read/writes. But it should be in the two to three digit miliwatt range which isn't much compared to the N100 itself which pulls 6W at idle, being an inefficient x86 space heater.

The Pi 4 4GB can idle at 1W using LPDDR4, the Pi 5 8GB using 50% more efficient LPDDR4x idles at... 3W. Meanwhile the average 12GB LPDDR5X Android phone can idle a whole week on a tiny 1 cell lipo (with power saving mode on), making this look so bad it's actually funny.

The long standing problem with Pi Foundation products is a complete disregard for any low power states, sleep or hibernation, so they probably don't do any RAM related power optimization either. It's only now with the RP2350 that they've finally implemented some kind of working sleep mode for the very first time in anything at all.

Marsymars• 2 years ago

N100 itself which pulls 6W at idle

That's not right - my entire N305 system takes 4-5W at idle.

quaintdev• 2 years ago

Genuine question what is the use case for such configuration I mean less RAM and powerful CPU?

I use my Pi for self hosting so I need more memory and more CPU is always better for my case. If they need less power consumption then they could have used Pi 4 or other lower version.

Besides low cost I don't see other advantage of such configuration. Please enlighten me.

mlyle4• 2 years ago

Pi 5's peak consumption is higher, but if you are doing the same amount of computational work (but a bit above idle) it is less.

Now this uses even less, and even the idle powers are comparable to 4. This wins in every way over Pi4, except cost.

tonymet4• 2 years ago

Given people typically use these for a home server or embedded controller, who cares about saving a couple watts?

1 watt savings idle? .72 kwh a month? in my area that's about 5₵ , even in california that's 40₵ / month / device ?

Are 1000-instance Pi arrays common? i can think of 100 better ways to get that amount of computing resources.

Aachen2• 2 years ago

If your needs are greater than a Pi but not at the level where you want to be buying professional server hardware, I can recommend checking if you or a family member still has a laptop they're not using anymore. Free hardware that would otherwise end up going to waste, and anything that had good performance in 2012 is still faster than a new Pi today. The older, the more likely it is to have replaceable RAM so you can stick in 16GB easily (older RAM types are also cheaper)

Max-q• 2 years ago

Maybe real time image processing from a camera. 2GB would probably be more than enough, and less power draw is nice when running continuously.

justin66• 2 years ago

For an embedded application involving signage or a kiosk, 2GB is probably plenty, and if you're doing enough of them the money saved would be worth it.

For a home user with one, or only a handful of, machines I don't think you'd necessarily need to save a few bucks this way. Although people obsessing over pennies is a theme in most Raspberry Pi threads, so there is clearly appeal for some.

georgeecollins• 2 years ago

I don't know if this configuration works for me, but unlike a lot of people here I have used Raspberry Pi's in robots. The 5's power consumption is such that it is a problem. The jensen nano is no longer supported. So maybe there is a "thingaverse" need for something more powerful then a pico /arduino but not so power hungry.

suprjami3• 2 years ago

Broadcom pushed the old Raspberry Pi SoC architecture as far as it would go, but it's hard limited to 1Gb RAM.

Raspberry Pi has become a development platform for Broadcom SoC, so they can sell the same chip in their corporate products and the cost of development is partially covered by Pi sales.

They also have an educational non-profit organisation, but don't mistake the Raspberry Pi for a 100% selfless endeavour.

Broadcom have been very hostile at taking Pi clones of the market. Look at that happened to ODroid's Zero clone with the same SoC as the Zero.

buildsjets2• 2 years ago

I frequently don't even install a GUI on most of my Pi projects, and barely use the capability that the hardware offers for my embedded applications. Why would I want to pay more money for capability and capacity that I will not use? That is stupid, and wasteful, and inefficent, and against my personal engineering philosophy.

So, the use-case is being tight wadded, skinflinted miserly old bastard who would prefer to put his extra cash toward yet another dumb old guitar, than DRAM that will be DEADBEEF for it's entire life?

Currently I am waiting on Adafruit to deliver a 2gb Pi 5 to run Klipper and Octoprint for my 3D printer. Explain to me why paying more of my money for 8gb would have been a smarter choice, given the difference in price accounted for about 20% of the cost of my most recent neato pawnshop guitar find, and the hardware more than exceeds the minimum capability for my needs? Please enlighten me.

moffkalast5• 2 years ago

Why do you need the horsepower of a Pi 5 to run Octoprint? There probably won't be a notable slicing speed difference compared to a Pi 4 and that was reasonably fast already.

PedroBatista2• 2 years ago

More memory also needs more power.

Not sure what percentage of those gains can be attributed to less memory and what can is due to better die/process.

kobieps• 2 years ago

Is the firmware still closed source?

written-beyond• 2 years ago

They've improved a lot, it's mostly the broadcom graphics firmware that still requires blobs. Probably because they've licensed the IP from somewhere else and the effort to reward ratio is too low.

mort96• 2 years ago

In other words: yes, the firmware is still closed source.

autoexec2• 2 years ago

I wouldn't mind them not using open firmware as much if we had unofficial alternatives that worked without sacrificing functionality, but I don't think anyone has managed that even after all this time.

alxjsn• 2 years ago

I rather just buy used Lenovo Thinkcentere PCs on eBay. Way more power, cheaper and relatively small. There’s a lot of different CPU/RAM/DISK configurations you can find.

I’ve been buying these, throwing Fedora IoT, docker, and Tailscale on them and running them from different locations for personal projects.

PedroBatista2• 2 years ago

Sure, if you need a machine to do "normal" PC/server things, buying a computer would be the natural path.

geerlingguy2• 2 years ago

There's also the Radxa X4 — Pi 4/5 form factor (tiny bit larger but not substantial), has a PoE HAT available, has 40-pin GPIO (with caveats, but it's basically a Pico strapped on the same board), and the N100's built-in GPU can run circles around the Pi or even RK3588 boards.

The efficiency isn't there, and you'll need to figure out a better cooling/case solution than the one Radxa ships, but I'm impressed by this little board.

If you can stretch your budget past $100 you can get a good brand new N100 or N305 system that will go further. Used gear is fine, but the power efficiency for anything in the $50-80 range used is pretty rough. Some people don't worry much about that, but in some parts of the world it can be $5+/month more to run older machines!

throwup238• 2 years ago

Some people don't worry much about that, but in some parts of the world it can be $5+/month more to run older machines!

California being one of the worst offenders, ironically. In SoCal my family and I pay (across several households) between $0.50/kWh and $0.99/kWh, so even a 15W idle can cost us at least $5 a month.

wpm• 2 years ago

I think your thermal pad issue was why yours ran so hot, I got one recently in the second batch and I so far haven’t been able to get it over 65C.

The pad I got was about 1-1.25mm thick, not crumbly like yours was on video. I assume they figured out what the issue was with their supplier.

Still think the entire thermal design is whack, a single fan perpendicular to the board on the end could draw air through the heat sink as well as over the SSD on the top. Working on whipping up some 3D printable stuff once I get some time next week.

bri3d2• 2 years ago

A few notes (as someone who is pretty staunchly anti-Pi-as-a-server, I end up having this debate often, and I do think there are reasons to do both):

* A Pi will sit much lower in total power consumption than almost any used PCs if both are doing effectively nothing (ie - simple, spiky tasks like filtering DNS, serving static content from RAM, etc.). You need to be doing something with the system before a PC server comes out ahead, and most people using a Pi as a home server... aren't.

Compared to a modern low-power x86 PC system, the difference isn't meaningful, but if you're buying used stuff 3 generations back, the difference becomes somewhat meaningful in terms of electric cost (on the order of tens of dollars per year, which is significant for hardware which cost tens of dollars to start with).

* The Pi of course has GPIO, SPI, etc. exposed, so you can use it as a nice "hybrid-IoT" device where it's a home server _and_ a sensor aggregator, for example. And the hat ecosystem, while generally insanely overpriced, is convenient.

Now, the moment you're running K8s/Docker or a real compute workload (security camera image recognition, etc.) you should probably move off of the Pi and onto something nicer, indeed. I absolutely never understood people running clusters of Pis or those goofy multi-Pi carrier boards. Just buy a real PC.

Aachen2• 2 years ago

A Pi will sit much lower in total power consumption than almost any used PC

For electricity consumption, beyond the wallet, it actually seems that hardware should have a lifespan on the order of decades before electricity consumption savings offset the environmental impact:

"For laptops and similar computers, manufacturing, distribution and disposal account for 52% of their Global Warming Potential (i.e. the amount of CO₂-equivalent emissions caused). For mobile phones, this is 72%. The report calculates that the lifetime of these devices should be at least 25 years to limit their Global Warming Potential." —https://wimvanderbauwhede.codeberg.page/articles/frugal-comp...

Rather than buying a new Pi, repurposing a 5-year-old laptop has advantages if this something one cares about. Desktops are quite a bit more hungry (I've heard this got better in recent years), but I can attest that a 2012 laptop still functions very well as a server, easily better than a 2024-era Pi. Probably I'll replace it in the next 2-4 years (so at ~15yo) when my current laptop finally will have given me enough grief (my inner grandpa complains they don't make 'em like they used to), and I'm not saying others must optimise for climate alone either, but it's something to consider when deciding on a good balance

sofixa• 2 years ago

I absolutely never understood people running clusters of Pis or those goofy multi-Pi carrier boards. Just buy a real PC.

A bunch of Pis allow you to run multi-node clusters on the cheap. If you're just experimenting with Kubernetes/Nomad/whatever, you don't need a lot of resources, just multiple nodes. It's easier and depending on config potentially cheaper than getting a beefier mini PC, throwing lots of RAM, and running VMs.

AshamedCaptain5• 2 years ago

* A Pi will sit much lower in total power consumption than almost any used PCs if both are doing effectively nothing (ie - simple, spiky tasks like filtering DNS, serving static content from RAM, etc.). You need to be doing something with the system before a PC server comes out ahead, and most people using a Pi as a home server... aren't.

That's not necessarily true since the Pis are particularly terrible at idle power consumption. E.g. the "power off" state consumption shown in the article is actually higher than the idle consumption of some low-power Atom/Celeron x86 chips. The Pi is just terrible at power management.

supertrope2• 2 years ago

To illustrate a Lenovo Thinkcentre m720s idles at 9W! Intel i5-8500 (6C/6T), 8GB DDR4, 256GB NVMe SSD. It cost $120.

jchw• 2 years ago

Emphasis on way more power. Granted, power draw isn't a huge problem for price reasons, since the cost of electricity is usually not that huge of a factor, but if you wind up running a lot of these, it can add up. More power draw is also a detriment if you want to keep things lean for longer battery, which makes me hesitant to put many older stock computers in the critical path of my network.

Don't get me wrong, though. Old stock computers are excellent for a wide variety of tasks, it's just that they definitely don't encroach on a lot of the use cases of modern SBCs. You needn't buy a Raspberry Pi 5 either; plenty of use cases like Home Assistant will run pretty well on a Pi 4 or even a Pi 3, and that's not getting into the many other reasons why a Pi may be interesting (like HATs, being able to use PoE power, GPIO, or even just the I/O in general.)

autoexec2• 2 years ago

I can't bring myself to buy Lenovo anything since they've repeatedly shipped products infested with malware, sometimes doing it in exchange for money. Once a company sinks that low and treats users with such disrespect I don't know how or why they should be trusted again.

gosub100• 2 years ago

I tried buying a used one on eBay and was disappointed to find it used a proprietary SATA power cable or connector,I can't recall. I hope they stopped doing that.

sgt2• 2 years ago

The ThinkCentres kinda look like "evil" IBM corporate machines out of a Star Wars movie. I wish I could put an IBM logo on mine to complete the picture.

sgt2• 2 years ago

I just bought one! It's brilliant, I had no idea. Cost almost nothing, and I removed the HDD and put an SSD in there, extra RAM and it's lightning quick.

Right now I have Windows 10 on it as I needed to run some old proprietary software, but it's a proper gem of a machine. I got the one without touch screen.

iwontberude• 2 years ago

Have 13 of them and I love them

Rebelgecko• 2 years ago

What's the break even point for the way more power vs the cheaper upfront cost? My raspberry pi has probably saved hundreds of dollars over the years in electricity vs what I'd have spent running a cheap Intel box

pseudosavant• 2 years ago

If they are using a standard 300mm wafer and have similar yields, the D0 stepping will allow them to get ~50% more chips per wafer than the C1 stepping.

hcfman• 2 years ago

Nice comparison. Looking forward to the 4nm version

ksec• 2 years ago

Again. The 33% smaller die and cost savings ( or at least room for Broadcom to charge them a little less ) is minuscule compared to the cost of DRAM.

While LPDDR are slowly approaching DDR5's level, we still need to find way to lower cost. It doesn't seems there are any breakthrough or idea to push production cost of DRAM down to $1/GB.

rldjbpin• 2 years ago

from the reading, my understanding is that the "dark silicon" was nothing but properly functional hardware which was redundant for use with rpi (e.g. ethernet controller).

if the makers knew what would not be required, why did they wait until the revision to make this change? the supply/demand argument does not make much sense to me especially given the surge in demand they've seen over the year, especially from the commercial arm.

New 2GB Raspberry Pi 5 has 33% smaller die, 30% idle power savings

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