I recently upgraded to a Ryzen 7 5800X3D and RTX 5070, paired with a 1440p monitor, Gigabyte B450M DS3H motherboard, and 16 GB of DDR4-3600 memory running in a 2x8 GB dual-channel configuration. In Rainbow Six Siege, even at the lowest settings, performance stays around 160–170 FPS. I expected considerably higher frame rates because Siege is generally considered CPU-heavy. The motherboard BIOS is updated, CPU temperatures are stable, and the graphics drivers are current. At higher settings the GPU reaches about 99% usage while the CPU sits around 30–35%; at low settings, GPU usage drops to roughly 65% while CPU usage remains near 30%. Is something limiting my performance, or are my expectations of 250–300 FPS unrealistic at 1440p?
4 Answers
First check whether the game is being limited by a frame cap, V-Sync, a monitor refresh-rate setting, or a driver-level setting. If GPU usage falls at low settings while the frame rate stays in the same range, the limit may be coming from the game engine, one or two CPU cores, or a cap rather than total CPU usage. Overall CPU usage can look low even when the game is maxing out a few cores.
Verify the memory configuration in Task Manager or the BIOS. Your 2x8 GB setup should be running dual-channel at around 3600 MT/s, with the correct memory profile enabled. That probably is not enough by itself to explain the whole difference, but slow memory or an incorrect configuration can reduce minimums and competitive-game performance.
At 1440p, the RTX 5070 can become the main limit once settings are raised, which matches the near-99% GPU usage you observed. At very low settings, 160–170 FPS may reflect a game or per-thread CPU limitation rather than the 5800X3D being fully loaded across all cores. Check per-core usage, clock speeds, temperatures, power plans, and whether an FPS limit is enabled before assuming the hardware is faulty.
Benchmark expectations need to match the exact Siege version, map, render mode, resolution, and test settings. A claimed 250–300 FPS minimum may come from a different setup or benchmark scene. Compare with a current benchmark using the same 1440p low settings, and monitor GPU clocks, CPU clocks, per-core utilization, and frametimes while testing.
The reported memory speed is 3600 and the modules are installed as 2x8 GB, so the RAM configuration appears correct.