I have an older Compaq Presario and the HP website says I can upgrade the stock Pentium 4 631 in my Alhena5 mobo to a Pentium D series Presler so I'm thinking about the Pentium D 630 with the same 3.0 clock speed as the Pentium 4. My question is since the Pentium D has somewhat higher power consumption do I need to think about upgrading my HSF as well or will the stock HSF suffice. Thanks for anyone's input. Matt.