That is what I heard two days ago coming from the study. Since the computer was switched off at the time, I could not trace the source. That evening the computer was as dead as a dodo and I realised with horror the two facts that I had got an exploded computer and that I had not backed up properly for several months. I know all the warnings...... A frantic call to my helpful brother gave me some hope all was not lost and sure enough the diagnosis was a burnt out power transformer pack (or something like that - a great big internal piece of equipment with loads of wires the technician showed me in his bin) expensive but fixable and the data intact. I have backed up immediately I got it back.

However, I write this, not as a warning to back up and really do it, but to ask how something like that could more or less explode when it was switched off and even then, plugged into a SurgeMaster. Was there anything I could have done to avoid it? I have started switching off the rocker switch power supply at the back of the computer when finished. Is that a good idea?

A computer that is only shut down is not truly switched off. It is in a 'stand-by' state. This meaning that most of the voltage lines that feed the computer parts have been removed. It remains like this until you press the button on the computer to boot it up again. For this to happen, part of the power supply must have the mains voltage applied to it all the time. It will be something in this 'permanently live' area that went BANG!, frightened the life out of you and cost you some money.

A surge protector won't prevent that happening if the cause of the fault was internal to the power supply. It would only help prevent any damage being done due a rise, spike or surge in mains voltage.

I always flip the mains switch when the computer is not in use, although that didn't stop the power supply packing in after about 6 years of use. It didn't go with a bang though. It just failed to power the computer up.

Does that also appy to the on/off rocker switch above the power plug at the back of the computer? That is not an extra protection?

Another thought, we do have quite a lot of electrical storms here in the mountains. I have an underground cable which supplies the modem which works the computer, TV and telephone, and the latter has to be on all the time or the burglar alarm company ring up enquiring about malfunction.

Some parts of the winter, the lot would have to be unplugged almost daily!