How to plug in a monitor

I have frustrating problems with computers all the time, and am totally reliant on internet sources to fix my problems.  So I thought I'd start writing down some of the problems I've had and how I fixed them, in case this can be useful to others.

I'll start things on a high by telling you about how I couldn't work out how to plug in a monitor.

I just had a refreshing 2 week holiday away from Oxford, then a week of conference/summer school work, and got back to the Oxford Computing Laboratory to find that my office had moved.  This was good news - my office mates and I are now in a larger, nicer office in a more sociable part of our building.  The minor downside was that I had to set up my computer (which was ready set up when I arrived at Oxford).

For someone with a degree and PhD in Computing Science, plus 2.5 years of experience with a very practical software company, this shouldn't be a problem, but being a bit of a dufus when it comes to real computers I couldn't get the monitor to show anything.

To cut a long story short, what I found out was that my machine has multiple DVI sockets on the back - there's a white DVI socket which looks like the regular one you should plug the monitor into, and that's what I was trying.  But then there are also 2 red DVI sockets (which look a bit different, they looks like they take more pins) at the bottom of the machine's case, on the back, which are apparently due to it having an external graphics card.

So, if you are like me and have this silly problem then look out for these mysterious additional DVI sockets!!  Of course you'll need a monitor to be reading this....