it really depends on the case and motherboard you're using... height can be a problem with some cases- the PSU is often right above the CPU so you need a low profile solution. other times, it's the capacitors that are in the way. in that case you need to find others who have successfully mounted a given HSF on that motherboard. if you're really unlucky, you're facing both issues.
but no way for us to advise you properly without a little more info.