It is responsible for generating a display on the screen and is easily damaged and prone to premature failure especially if abused.
If you disassemble a typical laptop your will usually see a heat sink with fan covering two large chips.
One will always be the CPU chip the other the graphics chip.
Both of these chips are very complex and generate a lot of heat during use.
The graphics chip though generates the most heat.
You will also see that the CPU is almost always contained in a quick release socket allowing it to be removed and replaced during an upgrade or repair.
The video chip, however, is almost never contained in a socket so cannot easily be upgraded or replaced.
As a general rule, the hotter a chip operates at, the shorter its life expectancy, when a failure can be expected.
So any measures that can be taken to keep this chip cool will extend the lifespan of the laptop.
There are a few obvious measures that can be taken to keep this chip cool and some less obvious ones.
Always use the laptop on a tray or table, not on a carpet, bed or on your knees as this will block the cooling vents.
Have the vents and fan cleaned if there appears to be a reduction in airflow or you hear the fan operating most of the time.
Different types of programs cause different amounts of heat to be generated by the graphics chip.
Games tend to make use of a lot of advanced graphics features so will generate considerably more heat than say a word processing program.
You will probably be surprised to find out that playing a DVD film will cause the graphics chip to run very hot, so potentially reducing the life expectancy of the laptop especially if this is done regularly.
If the wrong or an old graphics driver has been installed on the laptop then this may cause the graphics chip to overheat and will likely cause graphics intensive programs to hesitate or crash the laptop.
The correct graphics drivers are usually relatively easy to find and can usually be downloaded free from the manufacturer's Web site.
Upgrading the video chip on a laptop is usually almost impossible as it not possible to remove the old chip from the motherboard.
There are though, a few high specification laptops that have the graphics chip mounted on a separate sub assembly circuit board that plugs into the main motherboard.
This makes it easy, thought quiet expensive, to upgrade or replace the graphics chip as necessary.
Look after your laptop's graphic chip as it is either very expensive or impossible to replace.