When i boot up, after my pc has been off all night. i get a message before i enter windows saying my CPU fan is either off or running to slow, i checked and it is just running, but its slow. after i boot into windows it seems to run just fine. its running at about 3000rpm. its about 4 month. should i upgrade to a after market 20$ fan? if so anyone have a good suggestion for a venice 3200+ 939.