sounds like there is more going on..
I had the same problem, turns out there was a ram problem to... it had a short circuit and fried the ram.
if the fan starts, there is power. maybe not enough, you ll have to check that. ( measure it out if possible)
than check with new ram.
if still not working :
check with an extern monitor.
Check the flat cable and connection from mainboard to screen.
it is possible the chip on the graphic card is fried..
I was thinking on a dead motherboard , but the fan starts ... so i think more in the other components..
Let us know,
Kind regards
Kevin