It depends on the cable service you got your Tivo hooked up to.If your cable service is standard-definition (uses coax or composite to connect to a TV), then you can't use a computer monitor.If you have digital HDTV cable service and the cable box has a DVI or HDMI output, you can use any HDCP-compliant LCD computer monitor to display the HD cable box's video output.The video signal carried by HDMI is in fact single-link DVI, so a DVI-to-HDMI cable can be used to connect an HDMI cable box to a DVI monitor. And cable boxes ARE TV tuners (which is why they have remotes for changing channels), so the monitor does NOT require a tuner on-board to work with an HD cable box. It merely displays whatever DVI signal the HD cable box is telling it to display.Since broadcast-quality High Definition TV signals are at least 720p (1280x720 resolution), pretty much any LCD monitor can display 720p, as long as it is HDCP-compliant so it will work with the digital HD cable box.If you want 1080i broadcast HD, you should get an HDCP-compliant monitor that can display 1920x1080 resolution.Keep in mind most computer monitors have no speakers. You will have to hook up a separate set of speakers to the cable box to get audio.Hope this helps.