Due to its high airflow design, thermal performance of the Deepcool CL500 is excellent no matter how the case is configured. Even with the case in its default configuration with just a single 120mm exhaust fan installed, component temperatures such as the CPU and GPU are well under control when using a front-mounted AIO such as the Deepcool Castle 280EX.
Adding two 120mm fans to the top of the case had very little effect on component temperature, however, if a CPU air cooler is being used in the case, we would suggest adding a couple of front intake fans to pull cool air into the chassis.