On the positive side, you can scale out memory quite a lot, fill up PCI slots, even have memory external to your chassis. Memory tiering has a lot of potential.

On the negative side, you've got latency costs to swallow up. You don't get distance from CPU for free (there's a reason the memory on your motherboard is as close as practical to the CPU) https://www.nextplatform.com/2022/12/05/just-how-bad-is-cxl-.... CXL spec for 2.0 is at about 200ns of latency added to all calls to what is stored in memory, so when using it you've got to think carefully about how you approach using it, or you'll cripple yourself.

There's been work on the OS side around data locality, but CXL stuff hasn't been widely available, so there's an element of "Well, we'll have to see".

Azure has some interesting whitepapers out as they've been investigating ways to use CXL with VMs, https://www.microsoft.com/en-us/research/wp-content/uploads/....

:-/

But, because I'm a good sport, I actually chased a couple of those links figuring that I could convert Egyptian Pound into USD but <https://www.sigma-computer.com/en/search?q=CXL%20R5X4> is "No results", and similar for the other ones that I could get to even load

I think the main bridge chipsets come from Microchip (this one) and Montage.

This Gigabyte product is interesting since it’s a little lower end than most AXL solutions - so far AXL memory expansion has mostly appeared in esoteric racked designs like the particularly wild https://www.servethehome.com/cxl-paradigm-shift-asus-rs520qa... .

"CXL-GPU: Pushing GPU Memory Boundaries with the Integration of CXL Technologies" https://arxiv.org/abs/2506.15601

Do like the card though, was waiting for someone to make an affordable version (or rather: this looks affordable, I hope it will be both that and actually obtainable. CXL was kinda locked away so far…)

For a memory controller, that thing looks hot!