I have OC'ed my P4 3.0 @ 3.4 currently via by upping the FSB to 920(linking to memory as well), I have monitored my temp. at full cpu load it never broke past 51C on the Stock cooler. I was wondering do you think it is wise to OC to maybe 3.5-3.8? I also have another HSF that I bought http://www.newegg.com/Product/Product.asp?Item=N82E16835150056 . I also currently have AS5 on the cpu, I was wondering if I could go higher do you think I should use my other HSF or keep the stock Intel one. I noticed that the stock speed for the intel HSF is 2100 RPM while the Masscool one is 2400RPM.