I've never had memory training be forgotten with my AM4 nor LPDDR5-based laptops and NUCs. Is this a new thing with AM5 or something? Or just a certain brand of BIOSes?

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sspiff a day ago | parent [-]

It's a common issue on consumer boards with DDR5 and more than two DIMMs installed.

Doesn’t affect soldered memory or lower speed memory (like DDR4). Many memory controllers fail to achieve good speeds and timings at all on 4 DDR5 DIMMs, and fall back to running DDR5 at 3600MHz instead.

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magicalhippo 12 hours ago | parent | next [-]

Ok, so user selects too-high speed, controller tries for ages and fails, but doesn't save since it's overridden by user in BIOS?

I distinctly recall thinking my LPDDR5 NUCs were broken since they seemingly didn't boot the first time, until I recalled the training stuff. Took up to 15 minute on one of them. But neither has had any issues since, hence my question.

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justinclift 21 hours ago | parent | prev [-]

Wonder if DDR5 ECC ram has the same problem? I'm meaning the real ECC stuff, not the "on chip only ECC" that all DDR5 has.

	▲	sspiff 14 hours ago \| parent [-]
		The controllers which support ECC are usually a lot better and able to handle more channels. They also typically require active cooling.