If you're not planning to over-clock, just go with the manufacturer's heatsink. That's all I've ever used. Either the one included with the CPU for desktop machines, or in the case of Supermicro's workstation/server barebones, the included heatsink.
What ever Intel/AMD includes with their chips is good enough to cool them by design. Although I do usually clean off their thermal compound and go with Arctic Silver 5, just because it is easier to work with, and does seem to help cool a bit more.