Did you take toni's advice and install more ram because if you installed it wrong, you would get a blank screen. If you did nothing, then you will probably need to check if your CPU melted or your motherboard is fried or if you hard disk finally croaked.
There is a PREVIOUS! board in Windows ME
Because the computer was Windows ME until
I installed "WindowsXP/SP2"
So go to this site to review my problems.
And answer there please