So the Intel’s Core i7 (Nehalem) is supposed to be launched later this year and some of you folks may be eager to upgrade your system with Intel’s new invention. Core i7 requires an Intel socket 1366 motherboard instead of LGA775. No doubt, if you have an existing socket LGA775 motherboard but you're keen to upgrade your system to Core i7, questions regarding the new socket and compatibility with LGA775 are bound to arise. Frostytech labs has posted an article in attempt to answer your questions regarding the socket LGA1366 Heatsink.
“Will current Intel socket 775 heatsinks fit on Intel socket 1366 motherboards?
The reason is 'Nehalem' processors have somewhat different power specs, but more importantly the mounting pins which affix the heatsink to the motherboard are spaced further apart. For socket 1366 motherboards the holes are spaced 80mm apart, for socket 775 motherboard that distance was 72mm.” Read on
here.