How can I diagnose the 'beep code' error messages on my computer?

Q  I am having problems starting my PC. After I switch it on, I hear two beeps and, although I can hear the computer running, nothing else seems to happen.

On the odd occasion I have managed to get it working, I have run a virus check, but found no problems. The problem started about three weeks ago.
Chris Marshall

A  PC motherboards use ‘beep codes’ to warn of a problem that prevents the computer from starting properly – and from displaying a more informative error message on screen. The problem may not be serious and could be something as simple as a memory module or expansion card not properly fitted into its socket.

To determine the meaning of your particular series of beeps, though, you need to know the make and model of the motherboard. This will usually be listed in the motherboard manual supplied with the PC, which should also list its beep codes.

If not, search online for something like ‘[Your motherboard make and model] beep codes’ – and go from there.