For pure cooper heat-sink/fan, I pretty much stick with Zalman CNPS's. Depending on the size of your case I would say to go ahead and check this
Zalman CNPS7700-CU. I'm running an LGA 775 Prescott 3.2GHZ, the one known for being hot at
36C idle using the
ZALMAN CNPS7000B-Cu LED which I bought at compusa for $39.99 and $4.99 for the LGA 775 bracket.
THERMALRIGHT XP-90C it's just too much, plus you still have to buy the LGA 775 bracket and perhaps you will get the same results as with the Zalman which I don't think 36C at idle and 51C full load can be such a bad temperature settings. And that's a 90mm fan just like the CNPS 7000B.
Zalman 7700 or 7000.