You need a video card that has a video-in optionand connectors. most do not have this function but some do.

if your card does not include the option you can have a look at this pci card that is used with your video card,
http://www.softwareandstuff.com/CRD10186.html

Hauppauge WinTV-GO TV Tuner/ Video Capture Card-FREE SHIPPING!
$19.99

Condition: New
Warranty: 90 days


Your local computer store should hae this and many others for sale. you will be able to play your video games as well as watch tv.

good luck