And tell me why you think you need water cooling? It isn't an IBM System 390 mainframe is it? I have a custom dual CPU (8-core 3GHz), 8GB, 15TB workstation/server (2.5TB disc and 2 DVD recorders internal) that does just fine with air-flow cooling. Be more concerned with your power supply. If you are running multiple video cards that suck up a lot of watts, then the PS is critical, as is airflow. Any decent CPU fan and heat sink will generally do for the processors, but memory is more of a problem, and needs good airflow. Your water cooler will work with the CPU's ok, but probably doesn't deal with the other cruft, and it is that other cruft that will cause problems. My system when running at 100% cpu utilization on 8 cores will push the processor core temperature up to about 50 degrees Centigrade, but without adequate airflow, the memory temperatures reach over 105 degrees, at which point they start to fail. I can keep mine at 85 to 90 degrees with proper airflow, even under prolonged heavy load.