The Silent Wings 4 140mm PWM high-speed fans from be quiet are not directly compatible with the Dark Rock Pro 4 cooler if you consider the original mounting options. Here are some important points: - The Dark Rock Pro 4 comes with a 120mm and a 135mm fan and is designed for these sizes. - The mounting options of the Dark Rock Pro 4 are specifically designed for 120mm and 135mm fans and there is no official support or instructions for the use of 140mm fans. It is therefore unlikely that the Silent Wings 4 140mm PWM high-speed fans can be mounted on the Dark Rock Pro 4 without modification or customisation. If you want to refresh the cooler with new fans, it would be best to use the original 120mm and 135mm fans or look for alternative solutions that are specifically compatible with the Dark Rock Pro 4.