First, make sure the hard drive's interface and your DVR match. For instance, if you try to use a SATA hard drive with a PATA interface, you'll find that the plug and ports are incompatible. Second, you should make sure your DVR doesn't have a cap on how much storage you can add. The TiVo Series 1 set has a maximum single hard drive size of 137 gigabytes, though it has the capacity to hold two hard drives so you can double that. Third, you'll want a hard drive that spins at 7,200 revolutions per minute (RPM) or faster.
When you're ready, you'll need to unplug the device and remove the screws that hold the casing of your DVR together. Remember to avoid touching the power supply or you could receive a nasty shock. The hard drive should be easy to spot -- most look like a rectangular case. You may need to remove the hard drive from a special mounting bracket inside the DVR. Next, unscrew the hard drive from the DVR and disconnect the cables connecting the drive to the DVR's circuit board.
With some DVRs, the next step is easy. All you have to do is put your new drive right where the old drive was. You'll need to connect the cables to the drive and replace the screws to hold it in place. Once everything is back where it should be, you can plug in your DVR. It may take several minutes for your DVR to respond as it downloads the software it needs to run. But some DVRs require special software on the hard drive before they'll work. That requires making an image of the old drive.
Making an image of a drive is tricky. You need some experience with the Linux operating system. You'll also need some special cards and cables for your PC so that you can hook up your old and new DVR hard drives to your computer at the same time. You'll need to copy the contents of the old drive to the new drive. This process can vary from one brand of DVR to another and it can take a few hours or even longer. That's why many people opt for an upgrade kit -- it might mean losing your settings and programs, but you can plug the drive into your DVR and it should work just fine.
There are many resources on the Web that can guide you if you really want to tackle the upgrade as a do-it-yourself job. Remember to search for information about your particular DVR -- not every set of instructions will work with your equipment. Good luck!
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