If this is a new problem with an existing drive, did anything happen to the PC or did you make any changes between the last time it worked OK and the first time it didn't? If it's a new drive or you've added it as a second drive make sure it's properly connected and configured right in cmos/bios setup.
You should probably post back the drive model number and system specs.
If your old hard drive was an ide and the new one is sata you may have to set that in the bios options or set AHCI.
Really, more details would be very helpful so we do not have to guess. You have to be a little bit crazy to keep you from going insane.
