Will In-House CXL Development Undermine Their Own DRAM Business? Samsung, SK Hynix, and Micron Tech Simultaneously Abandon In-House CXL Controller Development

The world's three largest memory chip manufacturers have completely halted their independent research and development plans for CXL (Compute Express Link) controllers, turning instead to procure products from specialized chip design companies. This collective shift reflects a core contradiction in the memory industry: aggressively promoting in-house chips could cannibalize their most important revenue source—the general-purpose DRAM module market.

On July 20, according to a report by Korean tech media ZDNet Korea, Samsung Electronics, SK Hynix, and Micron Tech have all scaled back or abandoned their commercialization plans for CXL expansion device controllers. Montage Technology, Astera Labs, and PrimeMass, among other specialized chip design companies, are filling this void.

This change signifies that the division of labor within the CXL ecosystem is being reshaped, with memory manufacturers focusing on the manufacturing segment while design leadership shifts to independent chip design companies.

For the capital markets, this not only benefits relevant chip design enterprises but also means that the three major memory manufacturers will not engage in new competition around complete CXL solutions in the short term. Their core profit model will continue to revolve around traditional DIMM memory products.

The Three Major Manufacturers Adjust Strategies Successively

The pace at which the three companies exited in-house controller development varied.

Micron Tech took the most thorough action. According to reports, the company has closed its CXL controller R&D department and adopted PrimeMass's controller solution, with related products already entering Micron Tech's product catalog.

SK Hynix has formally notified partners of the termination of its in-house controller project and has reallocated its R&D team to the PIM (Processing In Memory) business, indicating its desire to concentrate resources on next-generation memory architectures with greater long-term competitiveness.

Samsung's adjustment was relatively cautious. According to reports citing semiconductor industry insiders, Samsung has removed its in-house CXL controller from its formal commercialization roadmap, retaining only frontier R&D projects. The team is currently mainly researching directions such as the combination of LPDDR and CXL.

Meanwhile, Samsung has shifted to external procurement of controller products. This means that the company's previously planned "in-house controller + CXL Memory Module (CMM)" integrated product has effectively been paused.

Why Did In-House Controllers Lose Appeal?

The initial vision of the three major memory manufacturers was highly consistent: integrate the controller and DRAM on the same circuit board and sell it as a complete solution to capture higher product value-added.

However, the market ultimately chose a different path. Data center customers prefer a modular architecture, where the controller is deployed independently on the motherboard and paired with standardized, low-cost DIMM memory modules. This approach not only reduces procurement costs but also retains flexibility for future upgrades and supply chain choices.

Changes in customer demand have placed memory manufacturers in a dilemma. If they insist on promoting integrated products, they must not only bear the R&D costs for controllers but also risk lower market acceptance due to higher prices; more importantly, if customers reduce standard DIMM purchases, it would instead impact the memory manufacturers' most core revenue source.

According to a report citing a semiconductor industry insider: If complete CXL products must compete directly with the company's DIMM business, the significance of promoting controller commercialization decreases substantially. Given the risk of cannibalizing core business, management finds it difficult to continue investing resources.

In other words, rather than cultivating a new market that might weaken the DRAM business, it is better to leave controllers to specialized manufacturers and continue focusing on memory manufacturing, where they possess the greatest scale advantages.

The CXL Ecosystem Enters a Phase of Specialized Division of Labor

Industry insiders believe that the exit of the three major manufacturers from in-house controller development does not mean abandoning CXL.

On the contrary, this resembles a typical specialization of labor during the maturation of an industry. Controller design is handed over to Fabless chip design companies, while memory manufacturers continue to leverage their manufacturing and DRAM technology advantages, creating value in their respective most competitive segments.

As this trend becomes established, Astera Labs, Montage Technology, and PrimeMass are expected to further consolidate their positions in the CXL controller market, while Samsung, SK Hynix, and Micron Tech can concentrate their R&D resources on areas with greater long-term value, such as advanced DRAM processes, HBM, and PIM.

From an industry chain perspective, the development logic of CXL has not changed; what has changed is the role of participants—memory manufacturers are no longer attempting to build complete platforms but are returning to supply chain division of labor. This also implies that the CXL ecosystem is moving from an early exploration phase to a more mature commercialization stage.