ok, try and follow this one if u can. Several weeks ago my computer started making a clicking noise,it starts out with one click..then picks up speed, to finally becoming a repetative clicking noise. The source of the noise is definately the hard drive. Now, my roomate who works for Geek Squad said instantly when he heard it that the hard drive is going bad! After running every possible diagnostic test imagineable, they never fail, it shows the hard drive passing everything. So, after 4 consecutive days and approx. 16 hours of troubleshooting with Dell Support , which included, running a full system diagnostics, unplugging the CPU fan and plugging it back in, unplugging the ram chips and plugging back in, unplugging hard drive from power supply and motherboard and plugging in, changing Bios settting numerous times, reformatting hard drive and reinstalling windows xp, and nothing seems to work. The noise occurs randomly, sometimes it happens on boot, sometimes it happens 2 hours later, sometimes it happens 20 minutes later..It has happened why surfing the net, it has happened while running virus scan, it has happened without doing anything at all! So Dells answer is that it is a software problem not a hardware. But, if I completely wiped the hard drive clean while reformating, reinstalled windows xp, and put the PC back to original manufactures settings, how could it be a software problem, when, for over a year, there have been no problems! Sometimes when the hard drive starts clicking, the computer locks up and gives me a blue screen error with Kernal_Input_Page_Error, with a code of 0x0000007a, I have also recieved one time a code of 0x0000004f Any Suggestions..My PC is a Dell Dimension 4700/P4 3.4mhz, 1 gig ram, 250 gig maxtor hard drive.