I just upgraded the CPU in an older HP desktop which I plan to use for software defined radio. It came with a sempron le-1300 2.3ghz single core. I installed a Phenom X3 8450 2.1ghz. I reused the heatsink and fan from the factory sempron. The temps are concerning me since they run from 49-55c at idle, and with BOINC running, they reach 70c. Passmark95 got the temp to 70c, at which point the fan went into super speed (which I've never heard it do before) and cooled it back to 62-64c. The fan stays in this very high rpm mode constantly in order to keep it at those temps. I didn't even know this fan was capable of that speed (or sound) before. The area of the heatsink that contacts the CPU is smaller than the processor. I used a generic silver thermal grease, which claims to be high performance, which I have even tried reapplying, with no change. I set power saving to balanced, instead of high performance, with no change. I'm assuming I need a new heatsink, but thought I'd post and ask for advice first. All replies appreciated. Thanks, Justin