Agreed really no reason to upgrade that old proc *shrug*
Anyways.. you may want to re-look at your AS III coverage on the processor... you may have too much (veryeasy to do, been there done that)
You want it razor thin covering the core.. anymore than that and it starts working like an insulator instead of a conductor

)
I also have the 2500 running at around 40C under full load

(not OC'd)
.. and thats with stock HSF