Abstract: Techniques are disclosed relating to testing whether a ray intersects a graphics primitive, e.g., for ray tracing. In some embodiments, intersection circuitry performs a reduced-precision conservative intersection test and shader circuitry performs an original-precision intersection test if the intersection circuitry indicates a hit. The intersection circuitry may quantize the ray (and may quantize the primitive or may receive a quantized representation of the primitive) and generates a potential error value based on propagation of quantization error for the primitive and ray. The intersection circuitry then determines an intersection result for the reduced-precision test based on the quantized primitive data and the potential error. In various embodiments, disclosed techniques may improve performance or reduce power consumption by reducing the number of original-precision intersection tests that do not result in hits.