Drive Doesn't Fit Into Bay

• If you are attempting to upgrade the hard drive in your laptop and the new drive doesn't fit, do not try to force it. Standard laptop hard drives are 9.5 mm in height, and the vast majority of laptop drives that you can purchase today are in this form factor. However, some older drives might be too tall to fit into your laptop's drive bay. If this is the case, you will not be able to use it.
  
  

Drive Does Not Insert Completely

• If your new hard drive does not fit completely into your laptop's drive bay, it is the incorrect type of drive. Laptop hard drives can be either ATA or SATA, two different technologies that use incompatible connectors. If the drive does not fit, do not attempt to force it, as you will break the connector. Exchange it for the other drive type. To avoid this scenario, examine the instruction manual for your laptop to determine whether it uses ATA or SATA hard drives before purchasing a new hard drive.
  
  

Drive Produces Too Much Heat

• Most laptop hard drives produced today spin at either 5,400 or 7,200 RPM. The benefit of a hard drive that spins faster is that it is able to read and write data more quickly, but 7,200 RPM drives can also produce more heat and noise than their 5,400 RPM counterparts. If you are concerned about the heat or noise generated by your laptop, look for a 5,400 RPM hard drive.
  
  

Drive Decreases Battery Life Too Quickly

• Hard drives are mechanical components, and their constantly-spinning motors can wreak havoc on a laptop's battery. If maximum battery life is a priority for you, upgrade your mechanical hard drive to a solid state disk (SSD), which uses flash memory instead of magnetic platters, and has no moving parts. Some SSDs consume as little as 0.1 Watt while in an idle state, and often transfer data faster than conventional hard drives, as well. Unfortunately, SSDs are still very expensive; spending over $400 for a high-quality SSD in 2009 will net you just 32 GB of storage space.
  
  

Drive Capacity Incorrect

• If the capacity of your hard drive is reported by Windows as being much lower than the drive's actual size, you may be attempting to format a very high-capacity drive using the FAT32 file system under Windows XP. Although Windows XP can use a high-capacity drive that is already formatted using FAT32, you will not be able to reformat the drive using that file system, because of a limitation of the operating system. Windows XP can only format a drive of up to 32 GB in size. To resolve this issue, format the drive using the NTFS file system.