If you want to expand the memory of your desktop PC, you only have one option: use the specific slots left free on the motherboard by populating them with conventional DIMM (Dual In-line Memory Module) modules.
That will change in the future, or at least that is what the consortium working on the CXL standard, which defines a new type of DRAM memory that can be added to desktop PCs via PCIe slots, wants. Samsung is already preparing its first products in this direction.
The CXL standard began to take shape in 2019, and soon had several giants in the tech world joining forces to develop it. These giants include Intel, AMD, ARM, IBM, Broadcom, NVIDIA, SK Hynix or Samsung.
The CXL 1.1 standard, which until recently was the most recent – CXL 2.0 was finalized in November 2020 – covered three different types of use cases: CXL.io, CXL.cache and CXL.memory.
It is precisely the third one that interests us the most, because with this type of scenario it will be possible to expand the RAM of our computer in an alternative way to the traditional one. Samsung is already developing this type of CXL.memory modules, and although the images for now are only renders, their appearance makes more or less clear the format in which we will find these curious modules.
The CXL.memory modules will work identically to a conventional module. It is not known whether they will be hot-swappable, nor what capacities they will handle, but it is known that they will be based on a PCIe 5.0 connection with an x16 link, allowing bidirectional bandwidths of 32 GT/s.
They will continue to be volatile memory modules (when you turn off the computer, whatever is stored in them will no longer be there), something that may change with the CLX 2.0 specification, which in one of the scenarios contemplates the use of persistent memory.
At the moment these modules are under development and therefore we do not know the availability date or prices, but it is expected that they may appear coinciding with the launch of Intel’s Sapphire Rapids processors, its next generation of Xeon CPUs for servers. Thus, it is likely that we will not see these modules in end-user desktops for some time.