My WD Elements Portable Hard drive does not mount or show on my desktop

Hi - I wonder If anyone can help - I recently purchased a 500 GB WD Elements portable hard drive. I reformatted it on my brother macbook which has mac os Snow leopard 10.6.8 and it shows and works on there but when I try to use it on my powerbook G4 17" laptop which has mac os x ( leopard ) 10.5.8 it does not mount at all on the desktop and does not even show when I use disk utlity - in addition it keeps making a clicking sound - does anyone know what the problem might be ?.

I went onto the WD websiite knowledge pages but could not find anything to help - closest solution was that there was not enough power in 2.0 usb port but this works when i use my lacie porsche hard drive no problems so I am a little stuck

Also can recommend a good portable hard drive to use with my powerbook - 10.5.8 mac os x - 2.0 USB - 500 GB storage - which is simple to use and works with Time Machine - thanks for any help - Jayas.