Video controller failed to initialize or respond

Hi

 

I wonder if someone can help. My 'old' Dimonsion 4300 is now used by my young daughter - mostly to use paint (she's only 5!) and annoy me with ms messenger.

 

A couple of days ago the screen failed to come on and after a checking all the connections etc, I opened the case and saw that the nVidia graphics card's (gforce 4200) fan seemed clogged with dust. A part of the nvidia cards fan cover had also looked like it had melted a bit. So, thinking it must be the card that has gone, I replaced it with another card I had spare. It still doesn't come one.

 

The lights on the back of the case show: Video controller failed to initialize or respond

 

Is this referring to the agp on the mobo? or the graphics card itself?

 

I would really appreciate any help, as she is now spending an hour (or so) a day, sitting there in front of a blank screen! I guess hoping it will simply come back on

 

Many thanks

Steve