You'll need to replace the hard drive in your PC for one of two reasons - either your current drive has experienced a hardware failure and needs replaced or you want to upgrade your primary hard drive for increased speed or capacity.
Replacing a hard drive is a relatively easy task that anyone can complete with a little help. In other words, don't worry - you can do this!
Note: If you're looking to simply add hard drive capacity to your PC, consider installing a second hard drive in your computer. However, if you need more space on your primary hard drive, you'll need to replace it with a larger drive.
Answer: To replace a hard drive, you'll need to backup any data you want to keep, uninstall the old hard drive, install the new hard drive, and then restore the backed up data.
The specific steps necessary to replace a hard drive differ depending on the type of hard drive you're replacing.
A PATA hard drive (formerly known as an IDE hard drive) is the older style hard drive with the 40 or 80 pin cables. An SATA hard drive is the newer style hard drive with the thin 7-pin cables.
Important: Are you replacing your primary hard drive that the operating system is installed on? If so, I highly recommend that you start fresh on your new hard drive with a new installation of Windows verses copying the entire contents of the old drive to the new one.
A fresh install of Windows will avoid any problems of data corruption or other software related issues that might have been present on your original hard drive.