This is good CAMM: here is (perhaps) the future memory standard for our PCs

Will the format of our computer memory sticks change? A new standard is emerging in the aisles of Computex in Taipei. If the classic DIMM (for desktop PCs) and SODIMM format strips still take center stage, this edition of the Taiwan technology fair is the first where CAMM2 modules are showing up.

After decades of elongated format strips that are installed in a thin location called slot in English, the CAMM format has the particularity of being placed flat and screwed onto a contact surface. Initially conceptualized and produced by the American PC manufacturer Dell for portable PCs, the format was adopted by the international memory standardization organization, JEDEC.

Why on earth did Dell, then JEDEC, go looking for a new format? Simply because it was designed on ancient concepts, current memory implies limitations. Thus, two modules are absolutely necessary to use the memory on two channels.

And the physical form, even of the modules (notably the SODIMM for laptop PCs), involves slowdowns caused by the physical arrangement of the memory modules not only on two different modules, but also on both sides of these two modules.

However, each centimeter traveled by information in a computer has a cost in latency and energy. In the CAMM2 standard, the internal circuitry is designed to provide the shortest path between the memory modules and the CPU. In short: with such a standard, a laptop PC could benefit from the speed of soldered LPDDR5 while being modular, which would allow capacity updates a posteriori.

Note, however, that although it seems suitable for general public PCs, the horizontal layout of the CAMM 2 standard makes it incompatible with the density needs of supercomputers and other data servers.

DDR5 CAMM for desktop PCs: the most visible at the show, but there is still work to be done

If the CAMM format was first designed for portable PCs, quite surprisingly, it is the format for tower PCs (desktop) which is most visible at Computex. Called DDR5 CAMM2, this rectangular format sits flat on the motherboard and locks with five screws.

If this seems easier to install than DIMMs, a manager of the G-Skill memory brand nevertheless specifies that “you must be careful when screwing to avoid deforming the support legs“.

A framework which means that this new module format, although promising, has limits. And will still require work from motherboard designers. “The positive side of this type of module is that its flat position makes it easier to cool, especially with watercooling. [refroidissement à eau, ndlr]. But on the one hand, we must review the design of the motherboards, particularly in the case where we want to integrate two modules; It takes up a lot of space! On the other hand, if one side of the module can easily be cooled, an air pocket between the module and the motherboard remains hot, which could cause stability problems.“, we were told.

And to add that “motherboard designers are working on it by studying metal plate devices on the back of the motherboard as well as heat pipes“.

When questioned by us, neither Asus nor MSI wanted to provide more details on this subject, each stating separately that “current motherboards are prototypes and we are still working on integration” of the DDR5 CAMM2 format.

LPDDR5 CAMM2: the most promising mobile format

LPDDR5 CAMM2 modules for laptops were barely visible at the show, and were often under glass. A Chinese module manufacturer producing for both HP and Lenovo, however, agreed to take it out of its box to allow us to photograph it. The format is logically more compact than that for a tower PC and its shape differs, with a flared lower part which accommodates various energy control components, etc.

Although no portable PC design equipped with a mobile CAMM2 module was visible at the show, we were nevertheless able to speak with a Taiwanese PC manufacturer, who preferred that the name of his brand not be mentioned. For him, the CAMM2 LPDDR5 format “is very interesting, and couples the modularity of the SODIMM with the performance of soldered memory chips“But he notes that the potential success of this new standard “involves work and investment. On the one hand, we need to evolve some of our motherboard design software tools. On the other hand, there is a tendency to solder modules, whether on motherboards or directly on the processor package. [comme avec le processeur Lunar d’Intel, ndlr] which is starting to represent some of the designs, particularly for ultraportables“, he notes.

According to him, the main obstacle to its adoption remains the price. “CAMM2 modules are currently not or rarely available and much more expensive than those in SODIMM format. Many laptop manufacturers would need to place large orders for LPDDR5 CAMM2 to bring prices down“, explains the engineer. Adding that “now that the standard is no longer under the control of DELL, but has been standardized by JEDEC, its technical advantages could help its development on high-power gaming or workstation type laptops“, he added. Without giving details of his company’s plans.

In the future, this type of memory will certainly require work to judge its relevance in tower PCs, but the format seems perfectly suited to workstation or gaming type laptops. It remains to be seen whether the gains (performance, modularity) will be sufficient to turn the industry around.