Zalman ZM-MC1 Power Connector from Power Supply to Fan 2x5V 2X12V (3pin) MFG Zalman MPN ZM-MC1 UPC 823884000139
Connect this adapter cable to one of your power supply 4pin molex IDE type power connectors and it gives you 4 3pin fan power connectors, 2 with 5 Volt and 2 with 12 Volt power. Use the 5V connectors to slow down and silence loud fans.