Want to turn your Windows 7-powered PC into a killer DVR, one that requires no monthly fees and has potentially limitless storage? Three new products will pipe your high-definition cable TV signals into your PC without even requiring you to open the computer's case.

When you use your PC to record shows, you’ll have a lot more freedom to do what you want with them. If you want to keep shows forever, you can. If you want to watch them on your phone or tablet, converting them is easy. And with (in most cases) a simple HDMI cable, you can watch them on your big-screen TV.

These three products--the Ceton InfiniTV 4 USB, Hauppauge WinTV-DCR-2650, and SiliconDust HDHomeRun Prime HDHR3-CC--each use a CableCard TV tuner from your cable provider. All are external, and all offer plug-and-play simplicity.

The Ceton and Hauppauge models require only a USB port, while the SiliconDust unit connects to your home router, allowing you to use it with more than one PC. They’re excellent products, one and all, able to supply two, three, or even four digital tuners for your multichannel viewing and recording pleasure. And all support SDV (Switched Digital Video), a bandwidth-saving technology that cable providers increasingly use (and require). Each device will record digital, HD, and premium channels, but not on-demand or pay-per-view programming.

Before you buy, however, call your cable provider and make sure that the company can give you a multistream (aka M-Card) CableCard--the essential requirement for all of these adapters. I ran my tests with a Comcast-supplied M-Card, which worked beautifully with all three.

Record Cable TV on Your PC, Easily Microsoft's Windows Media Center offers a program guide and manages recorded shows.

Likewise, check your PC’s specs. At a bare minimum, your system should have a dual-core processor, 3GB of RAM, and a DVI or HDMI connection to whatever display you wish to use. You also need a graphics card that supports HDCP copy-protected content. Fortunately, the Digital Cable Advisor tool found in Windows Media Center’s Extras Gallery will tell you in advance if your system has sufficient horsepower for this amazing extension of your HDTV.

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