I think it's just a vertical integration thing. They know what's in the machine and they can make sure that their suspend path puts every peripheral to sleep. Linux has no idea what's in your machine and there may be some device in there somewhere that freaks out if the machine goes to sleep without saying goodnight. Even a 50mW draw will destroy the suspend power budget. Chromebooks have similar vertical integration with respect to ChromeOS and they also enjoy long sleep life. Hypothetically an integrator like Framework can also guarantee this but I can't vouch for it being true, and they would not have any control over Ubuntu updates after the laptop is delivered to the customer.

Just to beat my favorite dead horse, this is why the insistence on SO-DIMMs "BEcAuse it's rEpAIrAble" has wrecked the reputation of a lot of laptops. DDR on a stick is fundamentally hostile to sleep power draw. Soldered-down LPDDR memory has always been massively superior for energy savings, and LP-CAMM finally solves the issue.

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Rohansi 7 hours ago | parent [-]

How does soldering memory help reduce sleep power consumption vs. using a socket? What is different other than how they are physically connected to the board?

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jeffbee 6 hours ago | parent [-]

It's not the form factor itself that is the problem. LPDDR is more efficient for various reasons and cannot be on a DIMM. It physically will not work with a socket. That is the problem that LP-CAMM solves: LPDDR but still removable.

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Koffiepoeder 5 hours ago | parent [-]

You did not answer the question.

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jeffbee 4 hours ago | parent [-]

Did I not? I'm trying my best here. The question is sort of off-target, though. What I am trying to say is: 1) DDR uses more power than LPDDR; 2) LPDDR cannot work on a DIMM socket, because of its lower voltage signals, and other reasons; 3) SO-DIMMs always contain the higher power DDR; QED) if you insist on SO-DIMMs, then you have to spend more energy.

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Koffiepoeder 4 hours ago | parent [-]

Rohansi was basically asking 'why', you keep on reiterating that DDR uses more power than LPDDR, but fail to answer why this is the case. Is it clock speed? Is it voltage? Is it a protocol/specification difference? 'various reasons' is not an answer.

	▲	ua709 4 hours ago \| parent \| next [-]
		There is no physics based reason why it couldn't work. If the industry really wanted to do it they could. But they don't. The primary reason is LPDDR just has too many pins. A DDR5 SODIMM has 262 pins and is an unwieldy beast. LPDDR5 has 644 pins. LPCAMM2 really shows the trade-offs. It adds a lot of bulk and cost, and repairability hasn't been valued high enough by the market to cover that overhead for most consumers. That's why Micron exited the market they played a big part in founding. https://www.ifixit.com/News/95078/lpcamm2-memory-is-finally-...
	▲	jeffbee 4 hours ago \| parent \| prev [-]
		LPDDR is very different from DDR so I don't really feel like diving into it in this tiny box. It has its own oscillators so the CPU doesn't have to clock it while asleep; it adaptively refreshes less often according to temperature; during self-refresh the cells are charged to a lower voltage that wouldn't really work for high-speed I/O but works fine for retention.