Connecting a computer to a big-screen TV is much easier than it used to be — not least because TVs are now little more than computer screens themselves.

Old fashioned glass cathode ray tubes have long since given way to the same kind of slimline LCD displays that laptops use and you need nothing more than a suitable cable to view your computer display on the living room telly.

While you wouldn’t want to use it for word processing (text will look fuzzy when seen from a comfortable distance), a big-screen TV is great for watching YouTube videos and playing games, but there are a few other things to think about before giving it a go. Here’s what you need to know.

Getting connected

An LCD HDTV (High-Definition Television) is essentially a high-resolution computer monitor with a TV tuner built in — only much larger, in most cases. In theory, that makes connecting a modern HDTV to a computer extremely simple, but complications arise, depending on what video-out sockets your computer has. Here are the ones you'll encounter:

TV sockets

HDMI

If you own a relatively new desktop or laptop PC, it will almost certainly have an HDMI video socket. This is the same kind of high-quality video-out socket found on Blu-ray players and digital video recorders, like BT's YouView.

HDMI port

All HDTVs from the last several years have one or more HDMI sockets, too, so all you need is an HDMI cable that’s long enough to reach from your computer to the TV. Better still, HDMI also carries an audio signal, so you’ll be able to hear your PC’s sound through your HDTV’s speakers.

The technical specifications for the HDMI standard supports cables up to 15 metres long, although half that distance is reckoned to be the maximum for trouble-free connections.

HDMI cable

If you do need a very long cable, be sure to buy a well-made one from a reputable supplier — though that should still only cost around £15. Paying much more than this for gold-plated connectors and other exotic materials is a complete waste of money, since it won’t affect the connection quality.

[Related story: How to connect your tablet to your TV]

DVI

If your PC doesn’t have an HDMI video-out socket, then it will almost certainly have a DVI socket. If your TV has one of these, too (refer to its manual), all well and good, but the chances are you’ll need an HDMI-to-DVI cable instead.

Cables with a DVI plug on one end and an HDMI plug on the other are widely available, else you can buy an inexpensive plug adapter for use with an existing cable. Unlike HDMI, DVI doesn’t carry an audio signal, so you’ll be stuck with your PC for sound unless you also run a suitable cable from your computer’s headphone socket to your TV’s line-in socket.

DVI port

You may encounter problems with copy protection technology called HDCP when using a DVI connection between a computer and an HDTV, so this option may not work with commercial video streaming services. If so, a straight HDMI connection is your only option.

VGA

If your computer only has a VGA video-out socket, you’re probably out of luck. Some HDTVs have a corresponding VGA-in socket, but most will need a VGA-to-HDMI converter to connect to a computer and these are too expensive to bother with.

VGA port

DisplayPort

Some PCs and many Macs have a DisplayPort video-out socket, but you’re unlikely to find a matching video-in socket on an HDTV. Suitable adapters are inexpensive, though, and DisplayPort also carries an audio signal.

[Related story: Audio and video connections explained]

What next?

With HDMI, DVI and DisplayPort, all you need to do is connect your computer, switch on the HDTV and switch it to the appropriate video-input (‘HDMI 2’ or similar) using the TV or remote control ‘source’ button.

TV remote copntrol

Your computer should then detect the new screen and reconfigure both displays accordingly, which usually means adding your HDTV as a secondary monitor that you can use in addition to your existing one.

The HDTV resolution should be set automatically, but if not, right-click on the Windows Desktop and choose Screen Resolution from the menu. Then choose the HDTV from the Display drop-down list and select either 1920x1080 (also known as ‘1080p’) or 1280x720 (also known as ‘720p’) from the Resolution drop-down list, depending on your HDTV’s specifications.

You’ll also need to choose Extend this display from the Multiple displays drop-down list (to use each screen separately) and you can drag the two displays around in this window to change their positions relative to each other.

Windows display setup

All that remains is to drag an application window to the HDTV Desktop and make it full-screen — look in its View menu (or similar) for this. For games, you’ll need to look in Video settings (or similar) for the option to use Display 2 (or similar). 

Do you connect your laptop or computer to your TV screen? Let us know in the Comments section below.