In a 4- to 6-quart saucepan or stockpot, cook sausage over medium-high heat, stirring frequently, until thoroughly cooked and no longer pink. Stir in drained tomatoes and green chiles, cover and cook 2 minutes. Stir in cheese and diced green chiles, reduce heat to medium and cook uncovered until melted, stirring frequently. Transfer to serving bowl, chafing dish or slow cooker. Serve hot with chips.