"we all go on about temps"
There's only one truth to remember where CPUs are concerned, and that is the cooler they are the better they'll run. There's no debate about that - it's a fact, and high operating temperatures will shorten the life of any processor. Take away the heatsink from an AMD processor and it would self-destruct in a matter of
Having said that, your Athlon 2000XP is rated to run at temperatures in excess of the 47 degrees you quote, although there's often confusion over what the temperature actually is. You must bear in mind that temperature sensors never record the core temperature of the processor, so the reading you get (from a sensor under the chip, or at the heatsink surface) is likely to be as much as 20 or even 30 degrees lower than the processor's real core temperature.
AMD state that a processor over 1,100MHz should never have a core temperature over 95 degrees, so from what I say above you can see that if your reading rises to around 60 degrees your processor is probably facing a melt-down. In practice I would tend to worry if the temperature rose to 50 degrees, which means you could be getting close to the safe upper limit.
My advice is to tolerate a little background noise and run the fan faster.