The cpu will remain at an idle temp especially if the system isnt processing any information. Even if the computer is idle when running windows the processor is still burning through a lot of information. A computer sitting at boot at pause will probably only produce enough heat to passively cool. and GhislainG the p4 series was normally very hot. that 60 degree wasn't a rare temp to see.
I guess it depends on the P4. I have two (one 2.8 one 3.2) and Hardware Monitor shows less than 40°C after being powered on for at least 5 minutes. They never reach 40°C, but it's 21°C in my office.