The CNPS7000A-Cu would be your best bet, absolutely silent on silent mode. However highly not recommended for overclocking.
-Intel PIV 2.4C @ 3.84G -Asus P4P800 -OCZ Gold 2x256 3700EL memory @ 256mhz 2.5-3-3-7 -Sapphire 9800pro @ 490/780 -SB audigy -80G Maxtor Diamond Plus9 Ultra ATA-133 hdd -450 Enermax PSU