Cover potatoes with 2 inches of cold water. Bring to a boil, add 1 tablespoon salt, and reduce to a simmer. Cook until potatoes are tender when pierced with the tip of a sharp knife, about 10 minutes. Drain; let cool 15 minutes.
Combine potatoes, cabbage, sour cream, oil, dill, and vinegar in a bowl; season with salt and pepper. Refrigerate 1 hour before serving.