Sounds rather more like a company behind the innovation curve pretending to "skip" the innovation as if to jump into a better innovation.
When the actual truth is they are sticking with the old thing. Reframed as a choice.
If "Ditching 4f" is such a good idea, why show their hand right before their competitors make the foolish choice of releasing it? Why not hold your cards until afterwards?
Unless perhaps this isn't a brilliant strategy but instead a spin for the investors?
Micron is regarded as a very technologically adept. The have a strong track record of delivering leading/performant dram without the manufacturing bells and whistles used by competitors. The CEO was one of the important engineers behind NAND flash back in the day
This is only good for Micron if 4F^2 is actually unachievable though.
If others end up making denser cells and Micron can't they will genuinely be behind. 6/4=1.5. It is not a small improvement.
I think this is definitely the "interest rates are high, dropping research and just pushing out what we already make gives us a higher valuation" type thing which can kill companies.
Micron is basically saying they have visibility on 3D DRAM and it’s not worth the impact to yields and effective capacity on the changeover to migrate to 4F2 for a couple generations. Very similar to their decision to delay EUV, which worked out very nicely for them.
It's a public company that is beholden to the shareholders. They have to explain what they are doing. But I agree with you, seems sus. Even if you can make more money by scaling the old tech today, that does not justify dropping the future innovation. Especially because by all accounts they are swimming in cash... Unless they are telling the truth and 4f extra complexity does not justify extra cost. I really have no context to evaluate that.
Sounds like innovator's dilemma to me. Their current production lines might be too profitable[0], so diverting expansion capacity to a yet unproven technology (to Micron's to-date profit margin requirements) might be too big of a financial hit. Since they're the ones who came up with 4F design, they must hold a ton of patents on the various incremental improvements. At which point, from a purely cynical and utilitarian view, it would make financial sense to let other players polish the remaining 20% and use patent portfolio as a wedge for mid-term technology transfers.
Or in short: "let others figure out the technical complexities and surrounding economics." - Which would make sense from a company that believes they can catch up once the expensive leg of the manufacturing/scaling research has been completed. Whether that bet is good or not, we'll see.
0: Didn't we read a few days ago here that all of 2027 production capacity has been sold out already?
Given that the stated plan of Micron is to focus on 3D scaling, keeping per-mm^2 production costs low makes perfect sense. When Samsung introduced their first volume V-NAND flash, the 2D feature sizes were larger than leading edge NAND flash because of the tolerances inherent in producing 90 layer flash (aspect ratio matters!) as well as the cost of production equipment. That trend has continued as it is cheaper to produce flash with more layers than to compensate for difficulties arising from decreasing amounts of charge kept in ever smaller cells.
In layperson DRAM-speak this translates to the following: rowhammer attacks are mitigated at the hardware level by increasing the size of and spacing between adjacent cells. At some point further feature size scaling makes it no longer be possible to produce 4F cells that are sufficiently robust against rowhammer type attacks to meet Micron's internal reliability targets. This would be akin to when Intel hit the power wall with the Pentium 4 in the early '00s forcing a change in engineering direction away from merely scaling clock speed.
With Micron's insight into the DRAM order pipeline, management likely has to factor in the chance of oversupply in the next couple of years as significant, which makes the shift in direction even more sensible. DRAM price crashes are a regular occurrence in the industry which lead to anti-dumping tariffs and legal battle in the 1990s (as well as Intel's shift away from DRAM towards complex logic devices in 1985). I'm pretty sure Micron's management is consciously working to avoid a repeat of that protracted legal battle.
I'd rather have an engineering problem over a legal problem any day of the week.
> Which would make sense from a company that believes they can catch up once the expensive leg of the manufacturing/scaling research has been completed. Whether that bet is good or not, we'll see.
The article mentions CXMT has committed to 4F^2 server RDIMMs by end of 2026, and a linked article mentions that CXMT has halved the fab build time from the industry-standard 2 years to just 1. How would Micron catch up with that?
The memory triopoly is in the midst of a slow motion wreck because pumping the brakes will reduce profits; the incumbents are going to have their butts handed to them by CXMT in 2-5 years, and they'll all act like they didn't see it coming as they are bailed-out by the US or SK government, for "National Security."
They really don't. A public company doesn't even have to provide forward-looking earnings guidance, though many choose to do so for strategic reasons. The only reason to make announcements is if there's some strategic benefit to doing so.
Well, yes, but wouldn't this fall under Regulation S-K, Item 303? They don't have to provide forward revenue guidance, but if they're exiting a line of business don't they have to disclose future trends and risks leading to that decision in their 10Q/10K?
> that does not justify dropping the future innovation
Looks like they have mapped the possible paths and consider it a dead end. The density increase is low compared to the effort to process cost, so they just opted for a simpler process with a similar density at a much lower cost per wafer. They might come back to it at some point - they invented it and have substantial IP investment on it.
Also, there might be some cost of opportunity - the AI bubble is now, so anything that diverts from current extremely profitable product lines is a terrible idea. It’s a bubble and they have the fiduciary duty to suck it until it’s dry.
> Sounds rather more like a company behind the innovation curve pretending to "skip" the innovation as if to jump into a better innovation.
This is not unlike the strategy the US employed to win the space race after they were quite behind in said race. It's a bold strategy, Cotton. Let's see if it pays off! (I'm not confident since I don't find the CEO to be anything more than a margin chaser).
A little hard to explain it to the shareholders. Yeah that expensive investment research project? A total fake out to mislead our competitors. We actually bought snacks and drinks for everyone with that money!
At idle, it doesn't take that much fuel to keep the engine alive. Idle stops are more important for noise abatement and local toxic exhaust gas emissions - a lot of exhaust gas treatment depends on the exhaust gas having a minimum amount of thermal energy.
The downsides of idle stops are, however, that they tend to put a lot of load on the engine, especially from the lack of oil pressure at the very few first strokes [1], and that the low temperature deposits all kinds of gunk in the exhaust pipework instead of transporting it outwards.
If you run an engine with idle stop, it really really is important to properly take care of the engine, including preventative maintenance and regular oil changes.
[1] That is even more of an issue in large engine blocks, hence that high pitched noise you hear from ships and locomotives for a while before they start up - that is an ancilliary oil pump, priming the entire oil pipework until all air is gone and full oil pressure is present at all ports in the system.
Yeah I disable idle stop on my cars, for exactly those reasons. If I'm going to be stopped for more than a minute or two, I'll let the engine idle so that temperatures can normalize, then shut it off manually.
Back when turbochargers became common on passenger cars, there was even advice to be sure you let the engine idle for a minute or two before shutting it off, so that the turbocharger could cool. Otherwise the oil in the turbocharger would get baked into a goo. Modern synthetic oils, and turbochargers, handle this better today but I still like to give any hot spots a chance to cool off.
> Back when turbochargers became common on passenger cars, there was even advice to be sure you let the engine idle for a minute or two before shutting it off, so that the turbocharger could cool. Otherwise the oil in the turbocharger would get baked into a goo. Modern synthetic oils, and turbochargers, handle this better today but I still like to give any hot spots a chance to cool off.
Yes, it was common to install a "turbo timer" that would leave the engine running at idle for a time after you shut off the ignition to let your turbo cool. I drive a 2024 factory turboed vehicle and it still recommends idling for 30 seconds to 2 minutes after parking before shutting the vehicle off and it continues running an electric cooling fan on a timer after you shut off the ignition.
The same set of challenges still exist in 2026 as did in 1986 for a turbo, for the most part.
> The downsides of idle stops are, however, that they tend to put a lot of load on the engine
While I don't doubt that it seems like this is essentially a solved issue. Priuses are some of the most reliable, long-lasting cars out there despite experiencing considerably more start-stop cycles than a traditional ICE with start-stop would.
Hybrids likely have more engineering around the start-stop cycles than full ICEs with start-stop bolted on to meet emissions requirements.
The prius style dual motor/generator planetary gear arangment avoids concerns about starter motor longevity. But the engines and how they're managed is tuned for their use case.
I'm sure ICE with start-stop will get there eventually, but the automotive industry tends to learn to build reliable drivetrains through a history of failure. From my experience with a couple rental cars a year, on user experience, start-stop is all over the map from really annoying to noticable but unobtrusive ... I imagine how design challenges around lubrication are met is also all over the map.
> Hybrids likely have more engineering around the start-stop cycles than full ICEs with start-stop bolted on to meet emissions requirements.
What evidence is there for this? The Prius was around for 12 years before Toyota brought their first production start-stop ICE to market, surely they (and other mfgs whose hybrids predate start-stop) didn't just throw away all of that knowledge to haphazardly "bolt on" a start-stop system. They didn't, which is why start-stop equipped card have things like low-friction coatings on their crankshaft bearings.
> The prius style dual motor/generator planetary gear arangment avoids concerns about starter motor longevity
Redesigned starter motors with improved longevity also avoid these concerns. In start-stop systems, the starter motor is a safety critical item and they are engineered to a much higher standard. As far as I can find, there's only one start-stop starter related recall in the US (Honda) and it wasn't even a mechanical issue.
> From my experience with a couple rental cars a year, on user experience, start-stop is all over the map from really annoying to noticable but unobtrusive ... I imagine how design challenges around lubrication are met is also all over the map.
I think this captures exactly why people fixate on these systems. They assume that because they can be janky to use (they often can be), that they must be jankily designed. I can't prove a negative, but I just haven't ever seen meaningful evidence that start-stop cars fail faster or fail in the ways critics suggest they should. Surely we would see some evidence of the extra spun bearings, sparkly oil, and premature starter replacements that this almost 20 year old tech has has wrought by now, right? The only evidence I've seen are slightly more expensive batteries needing to be replaced slightly more often.
> As far as I can find, there's only one start-stop starter related recall in the US (Honda) and it wasn't even a mechanical issue.
A start-stop starter issue seems more likely to be handled quietly with Technical Service Bulletins rather than a recall, IMHO. Unless the issue is a critical safety issue or is likely to affect every vehicle, manufacturers seem to prefer TSBs that have much less visibility than a recall. If you're lucky, the dealer will take care of it at your next scheduled service; but many TSBs are only taken care of if you specifically ask about trouble you're having and the dealer is aware of the TSB and you bring it up during the TSB period... my Ford hybrid had a major bearing issue and they replaced the whole motor/generator/transmission assembly under the TSB but only because I happened upon the TSB and brought it in specifically complaining... they had it for scheduled maintenance while it was exhibiting symptoms but it wasn't bad enough for me to complain and they didn't mention anything ... had I known to ask, I would have gotten a new replacement rather than a remanufactured, but oh well.
> They assume that because they can be janky to use (they often can be), that they must be jankily designed.
I think it's a fair assumption, because cars tend to be jankily designed or at least designed around the edge of viability. Most of the modern vehicles I've owned have had successful class actions about drive train problems that almost always come down to running things close to the edge to meet emissions requirements.
There's this one for start-stop https://www.carscoops.com/2025/08/honda-paying-millions-to-s... but there were a lot in the 2000s related to oil leaks etc related to running thinner oils for emissions. It's a consistent pattern; push the envelope for emissions, deal with the powertrain problems via class action.
> almost 20 year old tech
It's closer to 10-15 years old for the North American market, discounting systems used for hybrids because they tend to be significantly different.
> It's a consistent pattern; push the envelope for emissions, deal with the powertrain problems via class action.
Sure, I can definitely see that being a pattern, especially for things like modern Diesel emissions systems that are notoriously unreliable. I just haven't seen that pattern materialize for start-stop. You found the same recall I did, which for the mast majority of people was fixed with just a software update. Where are the class actions for these shoddily designed systems?
Up to 2022 the Prius' ICE barely had 70 kW of engine power, and (IIRC, take with a grain of salt) neither turbochargers nor compressors. The less capacity the engine has, the more abuse it can tolerate, and it likely was ridiculously overspecced in tolerances and thicknesses.
In contrast, your 100 kW+ average vehicle? Probably built for maximum profit margins.
A Prius isn't taking off from a stop under strictly ICE power. The electric motor in the transmission lowers the load on the ICE, certainly enough to let the engine oil pump generate operating pressure before it's really under load.
Well.. as so many things in engineering: it’s a tradeoff. Mechanically, it’s also very important to let the engine warm up and cool down before and after heavy load. Primary reasons for warmup are that the oil is more fluid on higher temperatures and metal is also less fragile when 50 or so degrees above freezing. Cooldown is especially important on turbo engines as the turbo on hundreds of thousands revs per minute and high temperature needs oil to be pumped through the bearings. If you turn it off after heavy load on engines that do not keep the oil running after motor shutdown, there is a chance that oil burns and gets stuck in the bearings, degrading performance or worst case breaking the turbo.
Also for the warmup case, tolerances inside the engine are designed assuming a hot engine. At lower temperatures, the metal hasn’t expanded yet causing also more stress on various parts such as the piston (seals).
And for the turbo I forget to mention that if you leave a turbo engine idle for a few minutes that this allows both the temperature and speed of the turbo to reduce. Many trucks have a sticker in the dashboard saying “do idle engine x minutes before shutdown to avoid turbo damage”. (But also do not idle for extended periods which I’m not 100% what’s the reason. I guess it’s due to diesel engines in some cases getting too cold while idling.)
When a combustion engine is idling, it’s usually not burning anywhere close to 100% of the fuel that it draws, which means higher quantities of unburnt fuel are reaching downstream parts of the engine system (like the exhaust system) that are only designed to be moderately resistant to fuel.
The externalized consequences of drivetrains failing faster (or being abandoned because they give the perception they might) easily offsets whatever gains are achieved with this nanny tech.
Auto start/stop is a great example of weirdly aggressive nerds failing to explore nuance, which is found everywhere.
In the early days it also killed starter motors as they weren't rated for that duty cycle.
I feel these kinds tech are more symbolic than functional and exist to simply check off boxes to obtain environmental ratings. I would even guess the environmental ratings are also short sighted and exist as symbolic gestures of environmentalism. Basically, environmentalism performance theater.
Having stood next to many cars starting after an idle stop, the start is barely louder than the idle. The area under the curve is far smaller for idle start/stop than it is for leaving the vehicle running.
When the actual truth is they are sticking with the old thing. Reframed as a choice.
If "Ditching 4f" is such a good idea, why show their hand right before their competitors make the foolish choice of releasing it? Why not hold your cards until afterwards?
Unless perhaps this isn't a brilliant strategy but instead a spin for the investors?
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