I've recently installed watercooling on the Asus A8N32-Sli mobo. The northbridge and southbridge are passively cooled using the heatpipe and a small heatsink. The heatsink is positioned between the CPU and a rear case fan. With air cooling the CPU this heatsink gets enough airflow to cool it but when watercooling is installed Asus tell you install this little blower fan to attach to this heatsink. This blower is exteremly noisy. As I want to have a very quiet PC it needed to go and to cool this heatpipe sufficiently I came up with this little mod. It's a plastic shroud that attaches to the rear exhaust fan and it directs air over the small heatpipe heatsink. With the exhaust fan running at 7v it reduces the mobo temp by around 3C with no extra noise Here are a few pics: