PSU PROBLEM!!!!!
I had an 040, and a 540Meg HD, it ran fine for a year, then started to crash alot... Then one night it just stopped. Dead.
The only clue I had to the problem was that one week before it died I heard a slight buzzing noise from the power switch when I turned it on. Sometimes when I tried to switch on the A1200 after it had died the Power light would glow dimly... I then decided to invest in a Goliath 150Watt PSU.
Problem solved. :-D
