Bottom line: Valve's decision to ship its latest Steam Machine with a single memory module is drawing closer scrutiny as early testing suggests that choice costs the system some performance. Benchmarks show that simply populating the second slot to enable dual-channel memory can deliver measurable gains in both compression workloads and several modern games.
Each retail unit ships with a single 16GB DDR5-5600 SO-DIMM, a configuration Valve links to tight DDR5 supply. That single stick forces the Steam Machine into single-channel mode out of the box, instead of tapping the extra bandwidth dual-channel offers.
Gamers Nexus benchmarked both configurations to see how much that choice affects performance. In side-by-side tests of the stock single-stick and a dual-stick setup, the outlet saw performance gains that depended heavily on the workload and peaked around 20%.
The contrast shows up most clearly in CPU-heavy tasks. In 7-Zip compression, two sticks were about 19% faster than one, a result that lines up with the extra bandwidth dual-channel provides. Decompression results were effectively identical, underscoring that not every workload leans on memory throughput.
In games, the picture is mixed as well, with some titles gaining a lot and others barely moving. In Baldur's Gate 3, the system averaged 69.4 frames per second with two sticks installed, compared to 60.2 FPS in the default configuration, a 15% increase. Resident Evil 4 showed a 10% bump, reaching 129.9 FPS versus 118.1 FPS. The Outer Worlds 2 posted a 14% gain, while Starfield saw a more modest 3% improvement.
Other games, including Black Myth: Wukong, Stellaris, and Final Fantasy XIV, showed little to no meaningful difference between the two setups. The tests suggest those titles are less sensitive to memory bandwidth, at least in the scenarios Gamers Nexus used.
The findings run counter to earlier comments from Valve, which had indicated that the performance difference between single- and dual-channel configurations would be negligible. The benchmarks show that claim doesn't hold up in every case, especially in tests that lean on system memory.
Valve has also clarified that all units currently shipping include the single 16GB module. Earlier guidance suggested buyers might receive either a 2x8GB or 1x16GB configuration, but that is no longer the case. As shipped, that leaves every unit running in single-channel mode until a second module is added.
The outcome isn't surprising. Running two sticks in dual-channel mode doubles the memory bus width, which can help in workloads that push a lot of data through RAM. Even with the higher speeds offered by DDR5, the difference between one and two channels remains relevant.
For most buyers, the stock setup will still feel fast enough, and the biggest gaps show up only in specific tests and games. Owners who care about squeezing out extra performance can add a second matching SO-DIMM to enable dual-channel, which pays off most in bandwidth-heavy workloads.