I got a Compaq Presario 5610 to work with that PowerLeap upgrade, works well.
However, I am finding that upgrading an older Compaq Presario to be EXTREMELY PAINFUL. The BIOS is really locked down tight with very few adjustments allowed. The BIOS won't even show me the hard disk I have installed.
Outside of the CPU upgrade, beware any further upgrade attempts on a Compaq Presario. Good luck!
-Mike