I got a new graphics card, RAM module and power supply for my birthday.
When I fitted them, being careful and taking all static precautions, the
thing did't work. After putting all the original stuff back and then
switching to an old motherboard I found that my motherboard was dead
but all the new stuff worked fine. Joy. I rushed out and bought a new
motherboard that still used the old interfaces of my existing and new
parts. It all seems to work well now which is a relief.