By "legacy" they probably mean that they work with the older process technologies, not that the fab itself is old:

The acquisition includes an existing 300 mm fab cleanroom of 300,000 square feet and will further position Micron to address growing global demand for memory solutions

In its May 2024 ’Hooray, we’re open!’ announcement, PSMC said it invested more than NT$300 billion (US$9.5 billion) on the facility, and that it had capacity to produce 50,000 12-inch wafers per month under 55, 40 and 28 nanometer technology nodes.

Those kinds of chips are still very useful for things like cars and washing machines and such where you don't need bleeding edge chip tech.

It's pretty clear that consumers are intentionally priced out of the market so they have to rent compute as a service.

Honestly I inherited an old Poweredge server and everything in it is dirt cheap. Like I can find RAM <1€/GB

One more thought

I don't think that, even if someone is willing to do so as a stopgap until memory production ramps up adequately, that it's possible to run Windows 11 on a DDR3-based system. DDR4 came out 12 years ago.

I'm not really a hardware person, but purely in terms of logic gates, making a memory circuit isn't going to be hard. I mean, a lot of chips contain internal memory. I'm sure that anyone that can fabricate a chip can fabricate someone's memory design that contains some amount of memory.

For PC use, there's also going to be some interface hardware. Dunno how much sophistication is present there.

I'm assuming that the catch is that it's not trivial to go out and make something competitive with what the PC memory manufacturers are making in price, density, and speed. Like, I don't think that if you want to get a microcontroller with 32 kB of onboard memory, that it's going to be a problem. But that doesn't really replace the kind of stuff that these guys are making.

EDIT: The other big thing to keep in mind is that this is a short-term problem, even if it's a big problem. I mean, the problem isn't the supply of memory over the long term. The problem is the supply of memory over the next couple of years. You can't just build a factory and hire a workforce and get production going the moment that someone decides that they want several times more memory than the world has been producing to date.

So what's interesting is really going to be solutions that can produce memory in the near term. Like, I have no doubt that given years of time, someone could set up a new memory manufacturer and facilities. But to get (scaled-up) production in a year, say? Fewer options there.

https://hanslabs.com/blog/2025-07-07-magnetic-core-memory-controller/

I mean you can't do it in your garage, but if you have the facility with the machines and the staff and the knowledge then yeah it's not hard.

There is actually a guy making CMOS transistors in his garage because he has some of the machines, but he can't make them micro-sized and can't make whole die sheets. (Also that's transistors for processors, not memory, but they parallel.)

The dirty stuff not so much but if you want it clean and pure yeah

I tried once, it didn’t go well.

rams into someguy3

No.

That's not really relevant. Just because they don't (won't) have the full vertical integration doesn't mean it won't have an effect. The chips are where there's a shortage. Most brands of assembled sticks of RAM don't make the chips. They buy the chips primarily from Micron, Samsung, and SK Hynix. If these chips become more plentiful, then brands like Kingston and GSkill can produce and sell the final product to consumers.

The real reason it won't help consumers, at least for a while, is that the plant won't be online until late 2027. And that's assuming demand doesn't increase in that time.