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Comment by Mistletoe | Hacker News Reader

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.

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.

You specified LP, they didn't.

It doesn't matter too much whether it's LP or not for idle, around 20% more at worst. It's at full BW util where it's close to double power consumption. That would still put it at less than half watt for full load.

Look for "AM62x Power Consumption" app note, page 5.

Similar for DDR5?

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

Yeah but unless you are deploying a bunch of them, its only like $3/year each

That's why many laptops run LPDDR these days.

My N100 from minisforum runs on 3.6W idle with 4-8W for medium to high cpu usage to 20W on full load with SSD, CPU, and integrated encoder loaded.

It is way more powerful than a pi and in low power mode as efficient.

I probably have the same N100 miniforums and can only get it down to 7w. Is it possible you could share how you got it down to 3.6W and 4-8W?

I just got this N100 a few weeks ago, have it on a killawatt next to my desk.

There are many tips here: https://gathering.tweakers.net/forum/list_messages/2096876 but I think the thing that did the trick was simply `powertop —-auto-tune`. I also disabled the wifi in the bios. I ran for a bit with turbo disabled which lowered the consumption a tiny bit and severely limited the peak usage, but it also made the system slow overall. So I enabled it again and now sometimes usage spikes but feels snappy. I’m running Fedora.

I have a ASUS PN40 and I got it to idle at 1.8W just by installing a Linux distro with almost no tuning whatsoever. (Just installing tlp which was at the time part of the suse laptop metapackage).

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).

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