This is the second in a short series that benchmarks a single RTX 5090 by re-running published Go solvers — programs that don't just play Go but prove the outcome under perfect play. The first installment was GPU-bound. This one is the mirror image: the graphics card sits almost idle while the CPU does all the work. So this piece is really about a CPU — and one number on it in particular.
What's being solved
117 classic life-and-death puzzles from Cho Chikun's well-known encyclopedia. Each asks one yes/no question: under perfect play, does this group live or die? You don't need to read Go — what matters is that the solver proves the answer exhaustively rather than guessing a good move. Five-minute budget per problem.
I rebuilt the RZS-TT solver from Shih et al. (A Study of Solving Life-and-Death Problems in Go Using Relevance-Zone Based Solvers, IEEE Transactions on Games 2025; rlglab/study-LD-RZ) and ran the full set on one RTX 5090 + Core Ultra 9 285K, using the paper's own config and 5-minute limit. The paper's reference machine was a single GTX 1080Ti with a Xeon E5-2683 v3 — about a decade older on both the GPU and the CPU.
The GPU is a spectator
