COUCHER, from what you say, I suspect that there is a memory problem. Do you get any POST beeps? If you don't then it is probably something else and you'll have to remove the plug-in cards drives etc to see if you can find what is preventing the boot up. However the diagnostics point to a memory problem, so if you have more than one stick of memory try only one of them. Also try removing and reseating the memory and polishing the contacts on the memory card with a clean cloth. You could also try running the memory at a slower clock rate if one is available. To do this you may need to reset your BIOS.