Path tracing
Path tracing is ray tracing that follows light along many random bounce paths per pixel, converging on a physically accurate image as samples accumulate.
Also known as full ray tracing, Monte Carlo rendering
Measured by SystemCheck
Part of the four-stage run: a 60-second sustained CPU load reporting throughput, decay and consistency; a memory stage reporting bandwidth and latency; a calibrated GPU raster load reporting frame time, pacing and decay; and a path tracer reporting samples per second. The paragraphs below say which metric carries this term.
Each sample traces a randomly chosen path through the scene, accumulating light contributions along the way. One sample per pixel is extremely noisy; the image converges as samples accumulate, with noise falling roughly as the square root of sample count. Real-time implementations trace very few samples and rely on aggressive denoising and temporal accumulation.
Because the work per frame is dominated by ray traversal and shading rather than by triangle setup, path tracing stresses a completely different part of the GPU than raster does. A card that looks strong in raster benchmarks can be middling here, which is why it deserves its own measurement rather than an extrapolation.
SystemCheck's fourth stage is a path tracer run over a fixed time. It measures samples per second and the consistency of sample delivery, so you see both raw ray throughput and whether your GPU delivers it evenly. Uneven delivery on a fixed workload usually means thermal decay, a power limit, or another process contending for the GPU.
Related terms