Place the potatoes in a pot with enough water to cover. Generously add salt. Bring to a boil, cook for about 10 minutes or until easily pierced with a fork. Drain, and transfer to a large bowl to cool.
Roughly chop peppers, celery and onions. Place in food processor, mince finely. In a medium bowl, mix the sour cream, mayonnaise, mustard, vinegar, salad cubes, celery, green onions and minced vegetables. Pour over the potatoes, and gently toss to coat. Add eggs, dill, garlic powder, onion powder, salt, and pepper. Mix. Best if chilled overnight before serving.