DLSS made my GPU feel new, but it revealed a CPU problem I didn't know I had

Using DLSS upscaling on an RTX 4090 at 1440p exposes CPU bottlenecks that are hidden at 4K. At 1440p, DLSS Quality renders internally at 960p, making games heavily CPU-bound and limiting GPU utilization to 80–85%. Frame generation can mask the issue visually but doesn't eliminate frame-time spikes or stutters caused by uneven CPU frame delivery. The author ultimately upgraded from a Ryzen 7 5800X3D to a Ryzen 9 9800X3D on AM5 to gain more headroom for DLSS at 1440p, concluding that a fast CPU is essential to fully benefit from DLSS upscaling — especially at lower internal render resolutions and high refresh rates.