Compression Attached Memory Module (CAMM) is a memory module form factor which uses a land grid array (LGA). CAMM can refer to both the general form and an early version developed by Dell. CAMM2 is the JEDEC-standardized version defined for DDR5 and LPDDR5(X).

Before 2022, most laptops used either SO-DIMMs or soldered-on memory modules. SO-DIMMs were developed in 1997 as a size-reduced version of the Dual In-line Memory Module (DIMM). Both are removable memory modules that use an edge connector ("slot"), which means that the contacts are all on one side arranged in a row. Because the faster memory of the DDR5/LPDDR5 generation is very sensitive to the synchrony of signals, a large amount of PCB area, both on the computer motherboard and the memory module itself, needs to be dedicated to carefully length-matched traces. The longer these traces get, the more power they waste, and the harder it is to keep the speed high while keeping the signals intact. In addition, empty DIMM/SO-DIMM slots create signal integrity stubs (SI stubs), degrading the achievable bus speed. Soldered-on modules do not have this problem, but they are not user-replaceable.

Dell engineer Tom Schnell developed the original version of CAMM. By replacing the edge connectors with a land grid array, many more pins can be connected at the same time with much smaller variation in trace length (and hence less extra trace length to match them). As a result, shorter traces are needed on the motherboard and the memory module PCBs, allowing the module to run at a lower voltage at higher speeds.

Compared to SO-DIMM, CAMM provides lower thickness, enables faster speeds above 6400 MT/s (hence higher bandwidth), and allows for higher capacities up to 128 GB per module on LPDDR5: features previously restricted to soldered-on LPDDR chips. DDR5 modules can reach 256 GB, for a total of 512 GB per double-channel slot in the stacked configuration.

On the other hand, CAMM sockets take up more area on the motherboard compared to vertical DIMM/SO-DIMM slots, and support two memory channels instead of one. As a result, motherboards can not generally provide spare CAMM sockets, due to space constraints and the fact that modern consumer CPUs generally only have two memory channels. A user who wants to add more RAM to their system will likely need to replace the existing CAMM module instead of simply adding another module.

CAMMs also cannot be replaced without tools as they use screws.

All DDR5 DIMMs have a power management IC to perform power regulation on-board, an answer to the need of more stable voltages. Extending along this line of thinking, there are DDR5 CUDIMMs and CSODIMMs with the ability to re-drive clock signals on-board. Other more established registered memory types also help with signal integrity.

There is no difference in performance between CAMM2 and DIMM modules configured to run at equivalent factory-supported speeds and timings. The advantage of CAMM2 lies in the relative ease of reaching higher speeds; there is no difference if higher speeds are not attempted.