Loud fan after following apple mac advice

Hi,

my mac computer was not starting up properly going into the boot up screen occasionally then at other times just not starting up osx and a very loud bleep sound when pressing the on button on the computer. Well, I followed apple macs advice to sort this problem out which is when you start up and you get the screen to 'mac boot' or whatever you type in
reset-nvram then press return then
reset-all then press return

I thought it worked fine just went straight into osx and then and it is driving me crazy each time I start the mac up a very loud fan comes on and DOES NOT TURN OFF what the HECK have I done? How on earth can I fix this? Please help!

mac osx 10.4.11, 1.8ghz power pc g5, 1gb ddr sdram

I wonder if your hard drive might be ready to die as they start giving trouble
noticed a g4 overheating when the hd died.

Oh right, I hope not I got the hard drive replaced a year ago! The problem is fixed now. I just unplugged all the usb and firewire devices and restarted it and it is fine now. Thanks for replying.