well, the absolute burn out temperature is 90 degrees Celcius, but recommended is anything at or below 50 Celcius. is yours a slot A or a socket A? if its a socket, its probably the Thunderbird core which is an incredible oven at max output. you should be running at about 45 Celcius ideally. any less than that, and your cpu fan is probably pretty loud.
hope this helps
oh and if nobody else has told you:
WELCOME TO TECHIMO!!!!
hardware
prices 
