Tell us what kind of Videocard you have, tell us what monitor you're currently using, and we can tell you what to look for. In general, there are 2 cables: VGA and DVI. VGA is a legacy cable, mostly for CRTs and very old LCDs. It provides good enough video out and is used on a large number of computers. DVI is a newer standard, for most LCDs and high definition televisions. It's a pure digital cable and provides superior image quality. If you're using a videocard with a VGA port and no DVI port, you will not be able to use a newer LCD. If you have a DVI port, you can use both(there is a DVI to VGA adapter).