This is a very minor problem but it is irritating me a lot.
I want to know, how can we find out which video/audio card are we using and also their drivers.

Hey Nisar, What make/model PC is it?

Its an assembled one.

The video and Sound may be built onto the Motherboard so power off, unplug power, slide the case off (at your own risk!) and checkout if there is a grphics card or if the monitor plugs direct to the motherboard. Either way take down the manufacture and any serial number and post back.

Oh okay.
I will do it.But i will give the details tomorrow as its really late now here and i am off to sleep.

Ok i opened the cover.
I ddint find any graphics card.The monitor does plug directly to the motherboard.
I tried to note down the details, but all writing was almost erased.So i couldnt see anything.

right click on "my computer" then click "manage" then "device manager" then "display adapters" & "sound, vidio and game controllers": you should see what's what. if you right click on an individual entry and choose "properties", you will then see the drivers.