Corsair and Crucial have launched high-density DDR5 memory modules with 24GB and 48GB capacities. Memory vendors have used Intel platforms to demonstrate the new memory kits. AMD's platform may be just as capable - with the correct optimizations.
It's important to distinguish between what's officially supported and what works. For example, Intel 12th Generation Alder Lake and 13th Generation Raptor Lake processors and AMD Ryzen 7000 (Raphael) Zen 4 processors officially support up to 128GB of DDR5 memory. So while higher capacity support (192GB) isn't entirely off the table, it depends on whether your chip can handle it. It's similar to the case of the official supported memory speed on processors and Intel XMP or AMD EXPO overclocking. Faster memory kits will work, but you're on your own, and your mileage will vary. Whether pushing the speed envelope or capacity threshold, the motherboard plays a vital role.
For example, MSI and Gigabyte (opens in new tab) claim that their respective Intel 600-series and 700-series motherboards are compatible with 24GB and 48GB DDR5 DIMMs without a firmware update. On the contrary, ASRock (opens in new tab) and Asus (opens in new tab) have released special firmware to usher in support of the new capacities. However, there's one thing in common; they're all Intel platforms, and there's not even one peep from AMD.
Twitter user MEGAsizeGPU (opens in new tab) got Corsair's latest Vengeance DDR5-5600 48GB (2x24GB) memory to post on his system powered by a Ryzen 5 7600X and ROG Strix B650E-E Gaming WiFi motherboard. However, the hardware enthusiast showed that while the system apparently posted OK, it was unable to enter the operating system due to a hardware error. The current AMD AGESA firmware may already support 24GB and 48GB DDR5 memory modules. If not, the memory training would fail, and the system will likely refuse to boot. Getting past the BIOS screen is progress, but it's evident that there's still a bit of room for optimization.
Presently, there aren't many 24GB and 48GB DDR5 options. Although Corsair and Crucial have unveiled their 24GB and 48GB DDR5 memory kits, only the former's offerings have arrived on the retail market, and they cost an arm and a leg. However, with Intel motherboards embracing the new memory modules, we expect AMD motherboards to catch up soon. As DDR5 continues to evolve rapidly, the 24GB and 48GB DIMM capacities will become more widespread.