Hi Ram,

Could you give us a little more information about your PC – for instance, you don’t say whether or not you have onboard graphics or a dedicated graphics card?

I suspect from what you have told me that the motherboard has onboard graphics.

First off, have you checked that your PCs monitor is working correctly?

You could try swapping out your monitor with a known working monitor – perhaps you could borrow one from a friend or relative if you do not have one spare?

Make sure when you try this to also try a different VGA lead and power supply cable just in case one of these is the cause of the problem.

Failing that, does the computer beep when you turn it on – is it going through the POST (Power On Self Test) successfully when you first power up your PC?

You say the PC runs but how have you determined that your PC is running correctly?

If your PC does have a dedicated graphics card then you could try re-seating it in case it has worked itself loose and lost proper connection with the motherboard (a pretty common problem this one).

If your PC has onboard graphics then you could try adding a dedicated graphics card to see if this cures your problem (enable this by going into the BIOS at power up and disabling onboard graphics).

Have you perhaps inadvertently selected a mode that your monitor cannot display correctly – try powering up your PC in Safe Mode by tapping the ‘F8’ key during initial power-up (for Windows Vista and Windows 7 you will need to hold down the F8 key during power-up, then select Safe Mode from a menu).

If none of the above suggestions help then I’m afraid it looks like you may need to try swapping out your motherboard.

All the best.