Based on Noctua"s signature NH-U12 series and fitted with the award-winning NF-P12 fan and NT-H1 thermal compound, the NH-U12DO forms a complete premium quality package that provides outstanding quiet cooling performance for AMD Opteron workstations and servers. The NH-U12DO"s SecuFirmTM mounting system screws directly to the standard backplate and makes the NH-U12DO a simple drop-in replacement for AMD stock coolers.