My computer is about 5 years OLD , recently the thing locked up in the middle of email , shut it down and it never came back . Hard drive goes through a series of clicks pressumably the read arm moving, then shuts off . When installed as the primary drive ,message comes up , no drive found . cant get it to run as a slave drive either .... [glb] HELP[/glb]Yep, sounds like the hard drive is finished. THATS the way mine sounded when it died. Sorry.We AGREE with Jw on this... unfortunately it is a definite sign of a hard disk drive failure when the hard disk drive MAKES a clicking noise or any abnormal noise and is not detected. You are also correct edoeler that it is likely the read/write head attempting to move that is causing this noise.I found an identical HD GOING to attempt changing the Board and anything else I can !!!!!!!!!!!!!!If by changing board you mean changing the hard disk drives interface board, I don't believe that is going to resolve your issue. This clicking noise is almost definitely caused by something such as the read/write head within the hard disk drive and something that will not be fixed by replacing the interface board.