I’d say the perfprmance issues are largely due to not the CPU lack of power, but to the game engine’s specifics. Doom 3 has a pretty peculiar engine architecture that was heavily criticised even back in the time as unduly relying on pure processor power at the time when GPUs were coming into the spotlight, lacking parallelism just at the introduction of multicore and muti-threaded CPUs, and its maniacal tendency to precache everything. Which go exactly against the test system strengths.

Elbrus CPUs are much more powerful tick-per-tick than the respective Intel chips, but they still lack the brute clock rate, and the engine design doesnt allow the powerful GPU to compensate for that. Again, the CPU’s ability for parallelism doesn’t match the game’s single-threaded nature, and the motherboard still uses the older KPI southbride with its limited throughput, which capped the disk system performance, while the game just loved to swap everything.

In fact, I believe that the test was not to demonstrate the system’s performance (which, bor the aforementioned reasons would still be on par with the lower-end i3s, I’d say, as they still go against the game’s peculiarities), but rather the compatibility, as they’ve built both the game, and the GPU driver from the source code, displaying the compiler’s compatibility with the existing standards and the overall interoperability of their OS and toolchain with the larger Linux comminity. Afer all, the ability to simply type «configure; make; make install» on any source code is a God’s gift for a platform, I’d say.