FWIW most "high end" boards automagically overclock CPU's a little bit (i.e. an extra 2-3MHz FSB) so that in benchmarks the PC provides a faster score leading people to say "wow this mobo made my computer xx faster in SuperPi" etc - this has also now spread to magazines

Well the bugger BSOD's my PC to the point of me ripping several hairs out over a week period before I noticed the problem.

Quote from S14 DRIFT :

Once I had changed this

...

yeeees?

Looks like it's time to think about sending my graphics card back. Nothing has worked so far. I'm gonna test it a little more, just to make sure, by giving to a friend who currently has on board graphics or something equally rubbish. I'll let him play some games with it for an evening or two and see what problems he gets.

Thanks for all the help and suggestions anyway. You certainly helped me come up with a lot of stuff to try, it's a shame it has all come to nothing so far but a broken card is a broken card. Unless it turns out that the card works fine in which case it's back to the drawing board.

I plan to be luckier next time I upgrade my computer!