Dead 41C?

[quantalume]

If the suggestions that Den linked to don't work, then I suspect that some of the internal connections may have become interrupted due to a broken screw post. One thing you can try in this case is to set the machine down on a desk and press firmly in all four corners while pressing the ON switch. Given the vintage of your machine, it may have nuts holding the CPU board in place, and in this case the four-corner method may not work. However, it's very rare that a 41C cannot be made to work again, given the required patience and skill.