Sid Meier's Civilization V

One more turn. It is always one more turn. Civilization V is the most reliable way I know to lose a Saturday afternoon to a game about building an empire from a single settler. For low-end hardware, it is the right Civ to recommend: newer entries push specs harder and the performance gap matters on budget machines. Enable Strategic View when performance dips and reduce map size. The hex combat system still holds up, the victory conditions are clear, and the diplomacy is just opaque enough to keep you second-guessing. Not the flashiest pick, but consistently the right one for older hardware.