Size up your drive

Laptop hard drives come in two sizes: 2.5 and 1.8 inches. The size depends on what type of notebook you're using. Most systems use 2.5-inch hard drives, while 1.8-inch drives appear mostly in ultraportable notebooks. Go to the manufacturer's Web site to find out which type your laptop uses.

I recommend: Sites like Newegg and Tiger Direct  sell drives in both sizes. For more choices, check out the Business.com page of hard drive providers.

The need for speed

Notebook hard drives come in three sizes: 4,200 rpm, 5,400 rpm, and 7,200 rpm. The drive speed refers to how fast the spindle rotates and how fast the data on the drive is being accessed. Both 4,200 rpm and 5,400 rpm drives use about the same amount of power, but 7,200-rpm hard drives will shave a few minutes off of your laptop's battery life. When shopping for a laptop hard drive, look for a 5,400-rpm drive for basic use and a 7,200-rpm drive for more intensive tasks like video editing and graphic design work.

I recommend: Check the specifications on any drive that you are planning to purchase to make sure that it will accommodate your needs. Once you’ve figured out your needs, head over to Amazon or SuperWarehouse.com where you can search for hard drives based upon the drive speed.

PATA vs. SATA

Internal drives are available in two varieties: SATA (Serial ATA) and PATA (Parallel Advanced Technology Attachment, which are also known as IDE or ATA drives). Prices and capacities are generally equal, but SATA drives are newer and therefore included in most new notebooks. To figure out which type your laptop uses, look at the back of the system. PATA connectors look like two rows of pinholes, if you don't see this, your notebook uses SATA. To double check, go to the manufacturer's Web site.

I recommend: Among the major notebook vendors, newer models from HP, Dell, Gateway, Acer, and Toshiba use SATA and Sony, Lenovo, and Fujitsu use PATA.

Internal or external?

While most of this guide deals with internal hard drives, external drives are a viable option for some. When choosing a new hard drive, you must first decide whether you want an internal or an external drive. Internal drives are inside of your PC and connect to the motherboard or interface card. External hard drives are separate devices that connect to your PC using either USB 2.0 or FireWire. If you're going to be using the drive for only one computer, an internal drive is your best bet. But, if you plan on sharing the drive between multiple PCs or are looking for a means to backup data, look for an external hard drive.

I recommend: There are only a few major players in this market and a drive from any of them should suit you well. For internal drives, check out: Hitachi, Seagate, or Toshiba. For external drives, go to: Hitachi, Western Digital, Seagate, or Iomega. You’ll also find both internal and external hard drives for sale in the Business.com storage devices directory.

Check with the experts

Read reviews of some of new models online from magazines and tech enthusiast sites. Although most manufacturers will serve you well, some brands fare better than others.

I recommend: Check out PC World, CNET, and PC Magazine for some of the latest hands-on evaluations.

Shop around

Like anything else, spending a few moments to compare prices can help you find a cheap laptop hard drive. Check out the big-box retailers and then head over and search through a few of the shopping aggregators, which automatically round up prices from across the Web. Also, look for rebates and online discounts.

I recommend: Circuit City, Best Buy, CompUSA, Price Grabber, and Shopping.com. For more deals look at the Business.com page of laptop suppliers.