alt Hacker NewsMeta reuses old RAM in new servers with custom bridge chip
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Why not go directly to the source article that has a lot more details?
https://www.theregister.com/systems/2026/06/29/zuck-saves-me...
The impressive part is not really reusing old RAM, its making the economics work despite the extra chip, software support and operational complexity
I have always wondered why there was never a big market[1] for "cheap PCI/PCI-X/PCI-e card you can stick a boatload of your old/surplus/n-generation old simms/dimms on and use as swap/slow memory/ram disk/etc". It's rare you can populate a motherboard with a full address space full of 'new' memory, and you can teach kernels to prefer some memory to others because of speed[2], so it seems like a no-brainer.
I seem to remember the market for doing similar with flash got neutered over patent issues, but I can't recall the details. And flash cache did end up being a market, at least for bigger players. Maybe something similar happened here, or maybe it just hit a niche I cared about at the time?
[1] I know there were a handful of products in this space, but my impression is they never really took off. I could be wrong. [2] Definitely can in NetBSD; I've done it for archs like VMEbus where it's common to have a small, fast on board memory and much slower, often larger memory out on the bus. I assume this sort of thing is enabled in Linux by the work to support NUMA, but I've never looked into it.
There are standard product CXL memory expander chips if you don't want to design a custom chip.
It’d be nice if there were a consumer version of this. I have plenty of old RAM.
ServeTheHome already reported on CLX memory expansion controllers back in December: https://www.servethehome.com/hyper-scalers-are-using-cxl-to-...
It will be interesting to see what happens to the consumer electronics market the next few years. Companies are right now gambling that consumers will pay extra because of RAM shortages. I suspect with the cost of everything else rising as well, a large portion of consumers (remember, HN, not everyone makes tech money) will just not be buying new devices for a bit.
The interesting part of this "RAM crisis" is similar to other fields where a problem results multiple parties looking for alternative solutions.
This yields for exciting ideas or workarounds that might result a post-crisis memory boom (hopefully) also for local machines.
1. Lowest, Apple is evaluating new Chinese manufacturer which means change of supply demand if indeed it has reasonable QA. (https://www.ft.com/content/f4ac5c92-03be-4499-b16a-017a7e9ee...)
2. Companies tries to workaround performance - suddenly single channel is 'ok' ? :) (https://www.gigabyte.com/press/news/2403)
From the paper:
"Our CXL solution achieves substantial gains for diverse workloads, including up to a 25% reduction in server count for disaggregated ML inference"
How does using worse RAM result in 25% reduction of server count for given workloads?
I am have an old Pentium 4 with RDRAM, think I could sell it to them? I think it has like 256MB. Haven't turned it on in awhile. Hope the first 640KB still work.
Thank you, LLM / AI dorks! I cannot even sensibly finance a proper homelab firewall / router these days, thanks to you and your agentic shit.
Literally the "new old thing":
https://www.andysarcade.net/store2/all-other-stuff/vintage-c...
ScholarlyArticle: "Vistara: Making CXL Real—Full Path from ASIC Design and OS Support to Hyperscale Deployment" (2026) https://aisystemcodesign.github.io/papers/isca26/vistara_cam...
TIL there are 2x 2.5GbE PCI-E HAT adapters for Pi 5.
How to attach RAM to the new NVLink/UALink fiber buses?
I wonder if it would ever start to make sense to burn an AI model into ROM, replacing a large portion of an inference machine's RAM with ROM. (Probably not, since I'm sure those machines do dual-duty and run training when the inference workload slows down)
With regards to RAM price I never understood the following: A 16GB RAM stick has 16*8=128 billion bits, with 1 transistor per bit, thats still 128B, yet its supposed to cost like $60 before the price hikes? In contrast, a 5090 GPU was $2000 (true it has RAM, but you're paying for the GPU ASIC really, I guess the rest of the GPU was less than $500), it had 93B transistors.
GPU transistors are smaller due to the more advanced process node (cost per transistor metrics aren't really clear, if they improve on advanced node or not, but I'd say they get cheaper as they get smaller, as technology costs are amortized).
I'm sure both RAM and logic use a process that is quite similar in both inputs and manufacturing steps. So while RAM is a commodity product, this insane price difference didn't make any sense.
So I guess when those fundamental inputs become a constraint, it would make sense for $/transistor move closer for both, which is a massive hike for RAM.
Wonder if Intel optain will would have made a huge comeback.
It'd be interested to see how one could leverage all the DDR3 ECC that they may have laying about; maybe an overseas shopping site has these boards available? Would DDR3 be as fast or faster than an SSD?
WE need to learn to use computing resources more efficently. Use RAM more efficently.Todays software just squanders computing resources.- like RAM
In the future, hardware is only for big companies to own. At least it seems we're heading that way.
Ram drives are making a comeback :)
Time to dust off my DDRDrive
Not terribly exciting at 1/10th the bandwidth and double the latency. That's a heavy price to pay to use old DDR4 memory.
There is already a data center oversupply. xAI rents out colossus and Meta also rents out capacity.
If they grow desperate I have GBs of DDR2 AND DDR3 in a drawer.
Who would have thought that the hardware I own didn't go down in value for the first time in my life but almost doubled in value.
if not the prices, no one would have implemented this in large scale solution..
how the mighty have fallen! Can't wait to see
Supply-demand economics really went awry in the age of chasing agi
At the beginning of William Gibson’s Neuromancer, the protagonist is trying to sell 3 MB of RAM in underground markets. This is often cited as one of the ways the book has not aged well. But, looking at the direction of the memory market now… maybe we just haven’t gotten there yet.