RunNvidiaPowerBench already performs a full internal ramp from 1 to N GPUs in Phase 2. Spawning N tasks with growing GPU subsets meant task K repeated all steps 1..K-1 already done by tasks 1..K-1 — O(N²) work instead of O(N). Replace with a single task using all selected GPUs. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>