Thanks, I shall make sure I have the latest graphics drivers installed.
It's a home built system, I can't remember when I replaced the hard drive - whether or not I put XP on it first or windows 7.
I don't think it's sound issues as such. Just it sometimes goes funny when the computer seems to hang. It could be the processor perhaps?
The processor and motherboard are the oldest components inside the computer but I'm happy to keep them if they work fine.
I have tried a couple of things since. I turned the 15 pin cable round just to see if there would be any change. Funnily enough I had a few black dots appear in part of the screen which would kind of move about then disappear. So I thought maybe it could be the monitor or cable. However I didn't think to try my TV till I was messing about and saw the VGA attachment - but that didn't solve the issue, so I have at least ruled the monitor and the monitors power cable, but not the 15pin.
Also I was after some new speakers for a while, which I've now replaced - so that's another thing I can rule out - same sound card though.
I'm gonna try the 15pin cable in another computer, and I guess I should try the computer straight in the mains and not the 6 plug attachment I've been using - to rule those out too.
I wonder why the computer is not connecting to my on board graphics any more? Since I haven't altered anything in the bios.