the first thing to do is determine if it really is a hard-drive failure you're confronting, and not one of the countless other equipment glitches that can cause a boot failure. If you have access to another computer, remove the failed hard drive from your sick PC, and hook it up as a secondary drive to the alternate computer. The easiest way to do this is through a USB universal drive adapter—it costs about $30 and is a good device to have around for all sorts of hard-drive diagnostics