edit* : I've recently found out that the Dell Precision T5400 is using standard Socket 771 (Server Socket). So this Adaptor can be used for any other LGA 771 Motherboards too, wich includes a lot of Servers. Good Heatsinks for this Socket aren't easy to find cheap.
I've recently bought an old Dell Precision T5400 Workstation PC. It had 1 Cpu installed and 1 empty socket. I've found a 2nd CPU but didnt find a original Heatsink for a reasonable price shipped to my Country.
So i bough an "Arctic Cooling Freezer 7 Pro" CPU Cooler and designed an adaptor to use it as a repalcement for the original "JD210" heatsink. --> works fine