There are several ways to back up using a hard drive. You can install a second internal hard drive in your PC and use backup software; you can set up a second internal drive to mirror the data copied to the primary drive; or you can connect an external drive to your PC via USB, FireWire, or eSATA cable.
A second internal drive with backup software is easy to set up, doesn't require the added power and desk space of an external drive, and is faster than an external drive. You can use backup software to perform all your backups for you, or you can drag and drop specific files.
Alternatively, you can set up the same internal hard drive to mirror the data from your main drive. With mirroring--also known as RAID 1, or redundant array of independent disks--your system automatically copies the contents of one drive to the other as you save files. This method was fastest in our tests. But unless your PC is already set up for this, doing it yourself is a little tricky. You might want to wait until you're in the market for a new PC, when you can have it configured for you. Dell offers an option called DataSafe that uses a form of mirroring to copy data from a primary drive to a second drive every time you save a file. The beauty of this backup method is that it's automatic and immediate, and you never have to configure and run backup software. It's also affordable. For instance, on the day we checked Dell was charging only $150 for its 250-gigabyte DataSafe option for a new PC.
If you're not ready to buy a new PC, picking an external hard drive is another option. External drives are slower than internal drives because the data has to travel across the USB, FireWire, or eSATA cable. On the drives we tested, backing up 1GB of data took anywhere from 1 minute for a relatively few very large media files to 2.5 minutes for a large number of small data files in multiple folders and subfolders. (1GB could represent tens of thousands of text files, about 250 songs, or about 285 digital images, depending on their resolution.) Because backing up large directories of small files typically takes longer, it could take at least 40 minutes to back up your entire iTunes library of 10,000 songs (40GB) and 1 hour and 40 minutes to back up the large directory of text files. Your results will also depend on the speed of your PC and the speed of the external drive.
Most external drives come with backup software, and some even let you back up with the push of a button. The only drawbacks are susceptibility to the same malware as your PC and the risks of losing your data to home theft or such disasters as flood or fire. For added security, we suggest coupling this means of backup with some form of offsite storage, such as online services, at least for your most irreplaceable data.
A relatively new development in external drives is the eSATA (external serial ATA) interface. eSATA is five times faster than USB 2.0's 60 megabytes per second, but unless your PC has an eSATA port--and it probably doesn't--you'll have to use an eSATA add-in card installed in a PCI slot. Some drives come with the card, but you'll have to install it yourself. What's more, even with the card you won't achieve the full advantage because PCI speed is limited to 132MB/s. We tested a drive using its included PCI card, and it performed about the same as the fastest USB 2.0 drives. If your PC is really old, you might even have USB 1.0 ports, which could make for excruciatingly slow data transfer no matter what external drive you choose. Consider upgrading.
Both external and internal hard drives are inexpensive; you can now get a 160GB drive for as little as $75. That's probably enough for a larger-than-average music and image collection, but those in the bigger-is-always-better camp can get a drive as large as 1 terabyte (TB). That's 1,000 gigabytes, enough to handle even the most enormous music and image collections. If you're into movies, that equates to dozens of hours of high-definition video.
A good choice for an external drive is the Seagate Push Button Backup External Hard Drive ST3300601CB-RK. It comes with excellent Windows and Mac software, a one-year warranty and one-button backup--the ability to initiate backup with one press on the drive rather than using an interface on the PC. If you have multiple PCs in your home, look for a network-attached storage (NAS) device. They typically cost more than regular drives, but their ability to retrieve data via your home network means you can store files from any computer on your network. The SimpleTech SimpleShare STI-NAS 250 offers excellent software for PCs and unlimited tech support
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Jan 05, 2011
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